ANTLR4 Grammar for ClickHouse and new parser (#11298)

.gitignore

@@ -125,4 +125,15 @@ website/package-lock.json
 # Toolchains
 /cmake/toolchain/*
 
+# ANTLR extension cache
+.antlr
+
+# ANTLR generated files
+/src/Parsers/New/*.interp
+/src/Parsers/New/*.tokens
+/src/Parsers/New/ClickHouseParserBaseVisitor.*
+
+# pytest-profiling
+/prof
+
 *.iml

.gitmodules

@@ -172,6 +172,9 @@
 [submodule "contrib/fmtlib"]
 	path = contrib/fmtlib
 	url = https://github.com/fmtlib/fmt.git
+[submodule "contrib/antlr4-runtime"]
+	path = contrib/antlr4-runtime
+	url = https://github.com/ClickHouse-Extras/antlr4-runtime.git
 [submodule "contrib/sentry-native"]
 	path = contrib/sentry-native
 	url = https://github.com/ClickHouse-Extras/sentry-native.git

CMakeLists.txt

@@ -257,6 +257,8 @@ if (WITH_COVERAGE AND COMPILER_GCC)
     set(WITHOUT_COVERAGE "-fno-profile-arcs -fno-test-coverage")
 endif()
 
+set(COMPILER_FLAGS "${COMPILER_FLAGS}")
+
 set (CMAKE_BUILD_COLOR_MAKEFILE          ON)
 set (CMAKE_CXX_FLAGS                     "${CMAKE_CXX_FLAGS} ${COMPILER_FLAGS} ${PLATFORM_EXTRA_CXX_FLAG} ${COMMON_WARNING_FLAGS} ${CXX_WARNING_FLAGS}")
 set (CMAKE_CXX_FLAGS_RELWITHDEBINFO      "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} -O3 ${CMAKE_CXX_FLAGS_ADD}")

base/common/defines.h

@@ -76,12 +76,6 @@
 #    define NO_SANITIZE_THREAD
 #endif
 
-#if defined __GNUC__ && !defined __clang__
-#    define OPTIMIZE(x) __attribute__((__optimize__(x)))
-#else
-#    define OPTIMIZE(x)
-#endif
-
 /// A macro for suppressing warnings about unused variables or function results.
 /// Useful for structured bindings which have no standard way to declare this.
 #define UNUSED(...) (void)(__VA_ARGS__)

cmake/warnings.cmake

@@ -24,7 +24,7 @@ option (WEVERYTHING "Enable -Weverything option with some exceptions." ON)
 # Control maximum size of stack frames. It can be important if the code is run in fibers with small stack size.
 # Only in release build because debug has too large stack frames.
 if ((NOT CMAKE_BUILD_TYPE_UC STREQUAL "DEBUG") AND (NOT SANITIZE) AND (NOT CMAKE_CXX_COMPILER_ID MATCHES "AppleClang"))
-    add_warning(frame-larger-than=32768)
+    add_warning(frame-larger-than=65536)
 endif ()
 
 if (COMPILER_CLANG)

contrib/CMakeLists.txt

@@ -21,6 +21,7 @@ endif()
 
 set_property(DIRECTORY PROPERTY EXCLUDE_FROM_ALL 1)
 
+add_subdirectory (antlr4-runtime-cmake)
 add_subdirectory (boost-cmake)
 add_subdirectory (cctz-cmake)
 add_subdirectory (consistent-hashing-sumbur)

contrib/antlr4-runtime

@@ -0,0 +1 @@
+Subproject commit a2fa7b76e2ee16d2ad955e9214a90bbf79da66fc

contrib/antlr4-runtime-cmake/CMakeLists.txt

@@ -0,0 +1,156 @@
+set (LIBRARY_DIR ${ClickHouse_SOURCE_DIR}/contrib/antlr4-runtime)
+
+set (SRCS
+    ${LIBRARY_DIR}/ANTLRErrorListener.cpp
+    ${LIBRARY_DIR}/ANTLRErrorStrategy.cpp
+    ${LIBRARY_DIR}/ANTLRFileStream.cpp
+    ${LIBRARY_DIR}/ANTLRInputStream.cpp
+    ${LIBRARY_DIR}/atn/AbstractPredicateTransition.cpp
+    ${LIBRARY_DIR}/atn/ActionTransition.cpp
+    ${LIBRARY_DIR}/atn/AmbiguityInfo.cpp
+    ${LIBRARY_DIR}/atn/ArrayPredictionContext.cpp
+    ${LIBRARY_DIR}/atn/ATN.cpp
+    ${LIBRARY_DIR}/atn/ATNConfig.cpp
+    ${LIBRARY_DIR}/atn/ATNConfigSet.cpp
+    ${LIBRARY_DIR}/atn/ATNDeserializationOptions.cpp
+    ${LIBRARY_DIR}/atn/ATNDeserializer.cpp
+    ${LIBRARY_DIR}/atn/ATNSerializer.cpp
+    ${LIBRARY_DIR}/atn/ATNSimulator.cpp
+    ${LIBRARY_DIR}/atn/ATNState.cpp
+    ${LIBRARY_DIR}/atn/AtomTransition.cpp
+    ${LIBRARY_DIR}/atn/BasicBlockStartState.cpp
+    ${LIBRARY_DIR}/atn/BasicState.cpp
+    ${LIBRARY_DIR}/atn/BlockEndState.cpp
+    ${LIBRARY_DIR}/atn/BlockStartState.cpp
+    ${LIBRARY_DIR}/atn/ContextSensitivityInfo.cpp
+    ${LIBRARY_DIR}/atn/DecisionEventInfo.cpp
+    ${LIBRARY_DIR}/atn/DecisionInfo.cpp
+    ${LIBRARY_DIR}/atn/DecisionState.cpp
+    ${LIBRARY_DIR}/atn/EmptyPredictionContext.cpp
+    ${LIBRARY_DIR}/atn/EpsilonTransition.cpp
+    ${LIBRARY_DIR}/atn/ErrorInfo.cpp
+    ${LIBRARY_DIR}/atn/LexerAction.cpp
+    ${LIBRARY_DIR}/atn/LexerActionExecutor.cpp
+    ${LIBRARY_DIR}/atn/LexerATNConfig.cpp
+    ${LIBRARY_DIR}/atn/LexerATNSimulator.cpp
+    ${LIBRARY_DIR}/atn/LexerChannelAction.cpp
+    ${LIBRARY_DIR}/atn/LexerCustomAction.cpp
+    ${LIBRARY_DIR}/atn/LexerIndexedCustomAction.cpp
+    ${LIBRARY_DIR}/atn/LexerModeAction.cpp
+    ${LIBRARY_DIR}/atn/LexerMoreAction.cpp
+    ${LIBRARY_DIR}/atn/LexerPopModeAction.cpp
+    ${LIBRARY_DIR}/atn/LexerPushModeAction.cpp
+    ${LIBRARY_DIR}/atn/LexerSkipAction.cpp
+    ${LIBRARY_DIR}/atn/LexerTypeAction.cpp
+    ${LIBRARY_DIR}/atn/LL1Analyzer.cpp
+    ${LIBRARY_DIR}/atn/LookaheadEventInfo.cpp
+    ${LIBRARY_DIR}/atn/LoopEndState.cpp
+    ${LIBRARY_DIR}/atn/NotSetTransition.cpp
+    ${LIBRARY_DIR}/atn/OrderedATNConfigSet.cpp
+    ${LIBRARY_DIR}/atn/ParseInfo.cpp
+    ${LIBRARY_DIR}/atn/ParserATNSimulator.cpp
+    ${LIBRARY_DIR}/atn/PlusBlockStartState.cpp
+    ${LIBRARY_DIR}/atn/PlusLoopbackState.cpp
+    ${LIBRARY_DIR}/atn/PrecedencePredicateTransition.cpp
+    ${LIBRARY_DIR}/atn/PredicateEvalInfo.cpp
+    ${LIBRARY_DIR}/atn/PredicateTransition.cpp
+    ${LIBRARY_DIR}/atn/PredictionContext.cpp
+    ${LIBRARY_DIR}/atn/PredictionMode.cpp
+    ${LIBRARY_DIR}/atn/ProfilingATNSimulator.cpp
+    ${LIBRARY_DIR}/atn/RangeTransition.cpp
+    ${LIBRARY_DIR}/atn/RuleStartState.cpp
+    ${LIBRARY_DIR}/atn/RuleStopState.cpp
+    ${LIBRARY_DIR}/atn/RuleTransition.cpp
+    ${LIBRARY_DIR}/atn/SemanticContext.cpp
+    ${LIBRARY_DIR}/atn/SetTransition.cpp
+    ${LIBRARY_DIR}/atn/SingletonPredictionContext.cpp
+    ${LIBRARY_DIR}/atn/StarBlockStartState.cpp
+    ${LIBRARY_DIR}/atn/StarLoopbackState.cpp
+    ${LIBRARY_DIR}/atn/StarLoopEntryState.cpp
+    ${LIBRARY_DIR}/atn/TokensStartState.cpp
+    ${LIBRARY_DIR}/atn/Transition.cpp
+    ${LIBRARY_DIR}/atn/WildcardTransition.cpp
+    ${LIBRARY_DIR}/BailErrorStrategy.cpp
+    ${LIBRARY_DIR}/BaseErrorListener.cpp
+    ${LIBRARY_DIR}/BufferedTokenStream.cpp
+    ${LIBRARY_DIR}/CharStream.cpp
+    ${LIBRARY_DIR}/CommonToken.cpp
+    ${LIBRARY_DIR}/CommonTokenFactory.cpp
+    ${LIBRARY_DIR}/CommonTokenStream.cpp
+    ${LIBRARY_DIR}/ConsoleErrorListener.cpp
+    ${LIBRARY_DIR}/DefaultErrorStrategy.cpp
+    ${LIBRARY_DIR}/dfa/DFA.cpp
+    ${LIBRARY_DIR}/dfa/DFASerializer.cpp
+    ${LIBRARY_DIR}/dfa/DFAState.cpp
+    ${LIBRARY_DIR}/dfa/LexerDFASerializer.cpp
+    ${LIBRARY_DIR}/DiagnosticErrorListener.cpp
+    ${LIBRARY_DIR}/Exceptions.cpp
+    ${LIBRARY_DIR}/FailedPredicateException.cpp
+    ${LIBRARY_DIR}/InputMismatchException.cpp
+    ${LIBRARY_DIR}/InterpreterRuleContext.cpp
+    ${LIBRARY_DIR}/IntStream.cpp
+    ${LIBRARY_DIR}/Lexer.cpp
+    ${LIBRARY_DIR}/LexerInterpreter.cpp
+    ${LIBRARY_DIR}/LexerNoViableAltException.cpp
+    ${LIBRARY_DIR}/ListTokenSource.cpp
+    ${LIBRARY_DIR}/misc/InterpreterDataReader.cpp
+    ${LIBRARY_DIR}/misc/Interval.cpp
+    ${LIBRARY_DIR}/misc/IntervalSet.cpp
+    ${LIBRARY_DIR}/misc/MurmurHash.cpp
+    ${LIBRARY_DIR}/misc/Predicate.cpp
+    ${LIBRARY_DIR}/NoViableAltException.cpp
+    ${LIBRARY_DIR}/Parser.cpp
+    ${LIBRARY_DIR}/ParserInterpreter.cpp
+    ${LIBRARY_DIR}/ParserRuleContext.cpp
+    ${LIBRARY_DIR}/ProxyErrorListener.cpp
+    ${LIBRARY_DIR}/RecognitionException.cpp
+    ${LIBRARY_DIR}/Recognizer.cpp
+    ${LIBRARY_DIR}/RuleContext.cpp
+    ${LIBRARY_DIR}/RuleContextWithAltNum.cpp
+    ${LIBRARY_DIR}/RuntimeMetaData.cpp
+    ${LIBRARY_DIR}/support/Any.cpp
+    ${LIBRARY_DIR}/support/Arrays.cpp
+    ${LIBRARY_DIR}/support/CPPUtils.cpp
+    ${LIBRARY_DIR}/support/guid.cpp
+    ${LIBRARY_DIR}/support/StringUtils.cpp
+    ${LIBRARY_DIR}/Token.cpp
+    ${LIBRARY_DIR}/TokenSource.cpp
+    ${LIBRARY_DIR}/TokenStream.cpp
+    ${LIBRARY_DIR}/TokenStreamRewriter.cpp
+    ${LIBRARY_DIR}/tree/ErrorNode.cpp
+    ${LIBRARY_DIR}/tree/ErrorNodeImpl.cpp
+    ${LIBRARY_DIR}/tree/IterativeParseTreeWalker.cpp
+    ${LIBRARY_DIR}/tree/ParseTree.cpp
+    ${LIBRARY_DIR}/tree/ParseTreeListener.cpp
+    ${LIBRARY_DIR}/tree/ParseTreeVisitor.cpp
+    ${LIBRARY_DIR}/tree/ParseTreeWalker.cpp
+    ${LIBRARY_DIR}/tree/pattern/Chunk.cpp
+    ${LIBRARY_DIR}/tree/pattern/ParseTreeMatch.cpp
+    ${LIBRARY_DIR}/tree/pattern/ParseTreePattern.cpp
+    ${LIBRARY_DIR}/tree/pattern/ParseTreePatternMatcher.cpp
+    ${LIBRARY_DIR}/tree/pattern/RuleTagToken.cpp
+    ${LIBRARY_DIR}/tree/pattern/TagChunk.cpp
+    ${LIBRARY_DIR}/tree/pattern/TextChunk.cpp
+    ${LIBRARY_DIR}/tree/pattern/TokenTagToken.cpp
+    ${LIBRARY_DIR}/tree/TerminalNode.cpp
+    ${LIBRARY_DIR}/tree/TerminalNodeImpl.cpp
+    ${LIBRARY_DIR}/tree/Trees.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPath.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathLexer.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathLexerErrorListener.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathRuleAnywhereElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathRuleElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathTokenAnywhereElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathTokenElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathWildcardAnywhereElement.cpp
+    ${LIBRARY_DIR}/tree/xpath/XPathWildcardElement.cpp
+    ${LIBRARY_DIR}/UnbufferedCharStream.cpp
+    ${LIBRARY_DIR}/UnbufferedTokenStream.cpp
+    ${LIBRARY_DIR}/Vocabulary.cpp
+    ${LIBRARY_DIR}/WritableToken.cpp
+)
+
+add_library (antlr4-runtime ${SRCS})
+
+target_include_directories (antlr4-runtime SYSTEM PUBLIC ${LIBRARY_DIR})

docker/test/fasttest/run.sh

@@ -131,6 +131,7 @@ function clone_submodules
         cd "$FASTTEST_SOURCE"
 
         SUBMODULES_TO_UPDATE=(
+            contrib/antlr4-runtime
             contrib/boost
             contrib/zlib-ng
             contrib/libxml2

src/AggregateFunctions/parseAggregateFunctionParameters.cpp

@@ -1,8 +1,8 @@
 #include <AggregateFunctions/parseAggregateFunctionParameters.h>
+
+#include <Parsers/ASTFunction.h>
 #include <Parsers/ExpressionListParsers.h>
 #include <Parsers/parseQuery.h>
-#include <Common/typeid_cast.h>
-#include <Core/Defines.h>
 
 
 namespace DB
@@ -25,6 +25,13 @@ Array getAggregateFunctionParametersArray(const ASTPtr & expression_list, const
     for (size_t i = 0; i < parameters.size(); ++i)
     {
         const auto * literal = parameters[i]->as<ASTLiteral>();
+
+        ASTPtr func_literal;
+        if (!literal)
+            if (const auto * func = parameters[i]->as<ASTFunction>())
+                if ((func_literal = func->toLiteral()))
+                    literal = func_literal->as<ASTLiteral>();
+
         if (!literal)
         {
             throw Exception(

src/CMakeLists.txt

@@ -6,18 +6,6 @@ if (USE_CLANG_TIDY)
     set (CMAKE_CXX_CLANG_TIDY "${CLANG_TIDY_PATH}")
 endif ()
 
-if(COMPILER_PIPE)
-    set(MAX_COMPILER_MEMORY 2500)
-else()
-    set(MAX_COMPILER_MEMORY 1500)
-endif()
-if(MAKE_STATIC_LIBRARIES)
-    set(MAX_LINKER_MEMORY 3500)
-else()
-    set(MAX_LINKER_MEMORY 2500)
-endif()
-include(../cmake/limit_jobs.cmake)
-
 set (CONFIG_VERSION ${CMAKE_CURRENT_BINARY_DIR}/Common/config_version.h)
 set (CONFIG_COMMON ${CMAKE_CURRENT_BINARY_DIR}/Common/config.h)
 
@@ -49,6 +37,7 @@ add_subdirectory (Dictionaries)
 add_subdirectory (Disks)
 add_subdirectory (Storages)
 add_subdirectory (Parsers)
+add_subdirectory (Parsers/New)
 add_subdirectory (IO)
 add_subdirectory (Functions)
 add_subdirectory (Interpreters)
@@ -186,12 +175,12 @@ endif()
 
 if (MAKE_STATIC_LIBRARIES OR NOT SPLIT_SHARED_LIBRARIES)
     add_library (dbms STATIC ${dbms_headers} ${dbms_sources})
-    target_link_libraries (dbms PRIVATE jemalloc libdivide ${DBMS_COMMON_LIBRARIES})
+    target_link_libraries (dbms PRIVATE clickhouse_parsers_new jemalloc libdivide ${DBMS_COMMON_LIBRARIES})
     set (all_modules dbms)
 else()
     add_library (dbms SHARED ${dbms_headers} ${dbms_sources})
     target_link_libraries (dbms PUBLIC ${all_modules} ${DBMS_COMMON_LIBRARIES})
-    target_link_libraries (clickhouse_interpreters PRIVATE jemalloc libdivide)
+    target_link_libraries (clickhouse_interpreters PRIVATE clickhouse_parsers_new jemalloc libdivide)
     list (APPEND all_modules dbms)
     # force all split libs to be linked
     set (CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,--no-as-needed")

src/Core/MySQL/MySQLReplication.cpp

@@ -799,9 +799,8 @@ namespace MySQLReplication
                 break;
             }
             case WRITE_ROWS_EVENT_V1:
-            case WRITE_ROWS_EVENT_V2:
+            case WRITE_ROWS_EVENT_V2: {
-            {
+                if (doReplicate())
-                if (do_replicate())
                     event = std::make_shared<WriteRowsEvent>(table_map, std::move(event_header));
                 else
                     event = std::make_shared<DryRunEvent>(std::move(event_header));
@@ -810,9 +809,8 @@ namespace MySQLReplication
                 break;
             }
             case DELETE_ROWS_EVENT_V1:
-            case DELETE_ROWS_EVENT_V2:
+            case DELETE_ROWS_EVENT_V2: {
-            {
+                if (doReplicate())
-                if (do_replicate())
                     event = std::make_shared<DeleteRowsEvent>(table_map, std::move(event_header));
                 else
                     event = std::make_shared<DryRunEvent>(std::move(event_header));
@@ -821,9 +819,8 @@ namespace MySQLReplication
                 break;
             }
             case UPDATE_ROWS_EVENT_V1:
-            case UPDATE_ROWS_EVENT_V2:
+            case UPDATE_ROWS_EVENT_V2: {
-            {
+                if (doReplicate())
-                if (do_replicate())
                     event = std::make_shared<UpdateRowsEvent>(table_map, std::move(event_header));
                 else
                     event = std::make_shared<DryRunEvent>(std::move(event_header));

src/Core/MySQL/MySQLReplication.h

@@ -549,7 +549,7 @@ namespace MySQLReplication
         std::shared_ptr<TableMapEvent> table_map;
         size_t checksum_signature_length = 4;
 
-        inline bool do_replicate() { return (replicate_do_db.empty() || table_map->schema == replicate_do_db); }
+        inline bool doReplicate() { return (replicate_do_db.empty() || table_map->schema == replicate_do_db); }
     };
 }
 

src/Core/Settings.h

@@ -399,6 +399,8 @@ class IColumn;
     M(Bool, enable_global_with_statement, false, "Propagate WITH statements to UNION queries and all subqueries", 0) \
     M(Bool, aggregate_functions_null_for_empty, false, "Rewrite all aggregate functions in a query, adding -OrNull suffix to them", 0) \
     \
+    M(Bool, use_antlr_parser, false, "Parse incoming queries using ANTLR-generated parser", 0) \
+    \
     /** Obsolete settings that do nothing but left for compatibility reasons. Remove each one after half a year of obsolescence. */ \
     \
     M(UInt64, max_memory_usage_for_all_queries, 0, "Obsolete. Will be removed after 2020-10-20", 0) \

src/DataTypes/DataTypeAggregateFunction.cpp

@@ -357,6 +357,8 @@ static DataTypePtr create(const ASTPtr & arguments)
             throw Exception("Unexpected level of parameters to aggregate function", ErrorCodes::SYNTAX_ERROR);
         function_name = parametric->name;
 
+        if (parametric->arguments)
+        {
             const ASTs & parameters = parametric->arguments->children;
             params_row.resize(parameters.size());
 
@@ -373,6 +375,7 @@ static DataTypePtr create(const ASTPtr & arguments)
                 params_row[i] = literal->value;
             }
         }
+    }
     else if (auto opt_name = tryGetIdentifierName(arguments->children[0]))
     {
         function_name = *opt_name;

src/DataTypes/DataTypeCustomSimpleAggregateFunction.cpp

@@ -72,6 +72,8 @@ static std::pair<DataTypePtr, DataTypeCustomDescPtr> create(const ASTPtr & argum
             throw Exception("Unexpected level of parameters to aggregate function", ErrorCodes::SYNTAX_ERROR);
         function_name = parametric->name;
 
+        if (parametric->arguments)
+        {
             const ASTs & parameters = parametric->arguments->as<ASTExpressionList &>().children;
             params_row.resize(parameters.size());
 
@@ -83,11 +85,13 @@ static std::pair<DataTypePtr, DataTypeCustomDescPtr> create(const ASTPtr & argum
                         ErrorCodes::PARAMETERS_TO_AGGREGATE_FUNCTIONS_MUST_BE_LITERALS,
                         "Parameters to aggregate functions must be literals. "
                         "Got parameter '{}' for function '{}'",
-                    parameters[i]->formatForErrorMessage(), function_name);
+                        parameters[i]->formatForErrorMessage(),
+                        function_name);
 
                 params_row[i] = lit->value;
             }
         }
+    }
     else if (auto opt_name = tryGetIdentifierName(arguments->children[0]))
     {
         function_name = *opt_name;

src/Dictionaries/getDictionaryConfigurationFromAST.cpp

@@ -99,6 +99,8 @@ void buildLayoutConfiguration(
     root->appendChild(layout_element);
     AutoPtr<Element> layout_type_element(doc->createElement(layout->layout_type));
     layout_element->appendChild(layout_type_element);
+
+    if (layout->parameters)
         for (const auto & param : layout->parameters->children)
         {
             const ASTPair * pair = param->as<ASTPair>();

src/Functions/GatherUtils/Sources.h

@@ -355,9 +355,9 @@ struct UTF8StringSource : public StringSource
 
     Slice getSliceFromLeft(size_t offset) const
     {
-        auto begin = &elements[prev_offset];
+        const auto * begin = &elements[prev_offset];
-        auto end = elements.data() + offsets[row_num] - 1;
+        const auto * end = elements.data() + offsets[row_num] - 1;
-        auto res_begin = skipCodePointsForward(begin, offset, end);
+        const auto * res_begin = skipCodePointsForward(begin, offset, end);
 
         if (res_begin >= end)
             return {begin, 0};
@@ -367,14 +367,14 @@ struct UTF8StringSource : public StringSource
 
     Slice getSliceFromLeft(size_t offset, size_t length) const
     {
-        auto begin = &elements[prev_offset];
+        const auto * begin = &elements[prev_offset];
-        auto end = elements.data() + offsets[row_num] - 1;
+        const auto * end = elements.data() + offsets[row_num] - 1;
-        auto res_begin = skipCodePointsForward(begin, offset, end);
+        const auto * res_begin = skipCodePointsForward(begin, offset, end);
 
         if (res_begin >= end)
             return {begin, 0};
 
-        auto res_end = skipCodePointsForward(res_begin, length, end);
+        const auto * res_end = skipCodePointsForward(res_begin, length, end);
 
         if (res_end >= end)
             return {res_begin, size_t(end - res_begin)};
@@ -384,19 +384,19 @@ struct UTF8StringSource : public StringSource
 
     Slice getSliceFromRight(size_t offset) const
     {
-        auto begin = &elements[prev_offset];
+        const auto * begin = &elements[prev_offset];
-        auto end = elements.data() + offsets[row_num] - 1;
+        const auto * end = elements.data() + offsets[row_num] - 1;
-        auto res_begin = skipCodePointsBackward(end, offset, begin);
+        const auto * res_begin = skipCodePointsBackward(end, offset, begin);
 
         return {res_begin, size_t(end - res_begin)};
     }
 
     Slice getSliceFromRight(size_t offset, size_t length) const
     {
-        auto begin = &elements[prev_offset];
+        const auto * begin = &elements[prev_offset];
-        auto end = elements.data() + offsets[row_num] - 1;
+        const auto * end = elements.data() + offsets[row_num] - 1;
-        auto res_begin = skipCodePointsBackward(end, offset, begin);
+        const auto * res_begin = skipCodePointsBackward(end, offset, begin);
-        auto res_end = skipCodePointsForward(res_begin, length, end);
+        const auto * res_end = skipCodePointsForward(res_begin, length, end);
 
         if (res_end >= end)
             return {res_begin, size_t(end - res_begin)};
@@ -495,7 +495,7 @@ struct IStringSource
     virtual bool isEnd() const = 0;
     virtual size_t getSizeForReserve() const = 0;
     virtual Slice getWhole() const = 0;
-    virtual ~IStringSource() {}
+    virtual ~IStringSource() = default;
 };
 
 

src/Interpreters/ActionsVisitor.cpp

@@ -757,6 +757,9 @@ void ActionsMatcher::visit(const ASTFunction & node, const ASTPtr & ast, Data &
 
     /// If the function has an argument-lambda expression, you need to determine its type before the recursive call.
     bool has_lambda_arguments = false;
+
+    if (node.arguments)
+    {
         size_t num_arguments = node.arguments->children.size();
         for (size_t arg = 0; arg < num_arguments; ++arg)
         {
@@ -919,6 +922,7 @@ void ActionsMatcher::visit(const ASTFunction & node, const ASTPtr & ast, Data &
                 }
             }
         }
+    }
 
     if (data.only_consts)
     {

src/Interpreters/AggregateFunctionOfGroupByKeysVisitor.h

@@ -97,10 +97,10 @@ public:
                               function_node->name == "any" || function_node->name == "anyLast"))
         {
             KeepAggregateFunctionVisitor::Data keep_data{data.group_by_keys, false};
-            KeepAggregateFunctionVisitor(keep_data).visit(function_node->arguments);
+            if (function_node->arguments) KeepAggregateFunctionVisitor(keep_data).visit(function_node->arguments);
 
             /// Place argument of an aggregate function instead of function
-            if (!keep_data.keep_aggregator && !function_node->arguments->children.empty())
+            if (!keep_data.keep_aggregator && function_node->arguments && !function_node->arguments->children.empty())
             {
                 String alias = function_node->alias;
                 ast = (function_node->arguments->children[0])->clone();

src/Interpreters/ArithmeticOperationsInAgrFuncOptimize.cpp

@@ -20,7 +20,7 @@ namespace
 
 const ASTFunction * getInternalFunction(const ASTFunction & func)
 {
-    if (func.arguments->children.size() == 1)
+    if (func.arguments && func.arguments->children.size() == 1)
         return func.arguments->children[0]->as<ASTFunction>();
     return nullptr;
 }

src/Interpreters/DDLWorker.cpp

@@ -1412,9 +1412,9 @@ BlockIO executeDDLQueryOnCluster(const ASTPtr & query_ptr_, const Context & cont
 
     if (const auto * query_alter = query_ptr->as<ASTAlterQuery>())
     {
-        for (const auto & command : query_alter->command_list->commands)
+        for (const auto & command : query_alter->command_list->children)
         {
-            if (!isSupportedAlterType(command->type))
+            if (!isSupportedAlterType(command->as<ASTAlterCommand&>().type))
                 throw Exception("Unsupported type of ALTER query", ErrorCodes::NOT_IMPLEMENTED);
         }
     }

src/Interpreters/ExpressionAnalyzer.cpp

@@ -423,11 +423,11 @@ bool ExpressionAnalyzer::makeAggregateDescriptions(ActionsDAGPtr & actions)
     for (const ASTFunction * node : aggregates())
     {
         AggregateDescription aggregate;
-        getRootActionsNoMakeSet(node->arguments, true, actions);
+        if (node->arguments) getRootActionsNoMakeSet(node->arguments, true, actions);
 
         aggregate.column_name = node->getColumnName();
 
-        const ASTs & arguments = node->arguments->children;
+        const ASTs & arguments = node->arguments ? node->arguments->children : ASTs();
         aggregate.argument_names.resize(arguments.size());
         DataTypes types(arguments.size());
 
@@ -820,6 +820,7 @@ void SelectQueryExpressionAnalyzer::appendAggregateFunctionsArguments(Expression
 
     /// TODO: data.aggregates -> aggregates()
     for (const ASTFunction * node : data.aggregates)
+        if (node->arguments)
             for (auto & argument : node->arguments->children)
                 getRootActions(argument, only_types, step.actions());
 }

src/Interpreters/GroupByFunctionKeysVisitor.h

@@ -105,7 +105,7 @@ public:
     {
         if (auto * function_node = ast->as<ASTFunction>())
         {
-            if (!(function_node->arguments->children.empty()))
+            if (function_node->arguments && !function_node->arguments->children.empty())
                 visit(function_node, data);
         }
     }

src/Interpreters/InterpreterAlterQuery.cpp

@@ -56,8 +56,9 @@ BlockIO InterpreterAlterQuery::execute()
     PartitionCommands partition_commands;
     MutationCommands mutation_commands;
     LiveViewCommands live_view_commands;
-    for (ASTAlterCommand * command_ast : alter.command_list->commands)
+    for (const auto & child : alter.command_list->children)
     {
+        auto * command_ast = child->as<ASTAlterCommand>();
         if (auto alter_command = AlterCommand::parse(command_ast))
             alter_commands.emplace_back(std::move(*alter_command));
         else if (auto partition_command = PartitionCommand::parse(command_ast))
@@ -124,8 +125,8 @@ AccessRightsElements InterpreterAlterQuery::getRequiredAccess() const
 {
     AccessRightsElements required_access;
     const auto & alter = query_ptr->as<ASTAlterQuery &>();
-    for (ASTAlterCommand * command : alter.command_list->commands)
+    for (const auto & child : alter.command_list->children)
-        boost::range::push_back(required_access, getRequiredAccessForCommand(*command, alter.database, alter.table));
+        boost::range::push_back(required_access, getRequiredAccessForCommand(child->as<ASTAlterCommand&>(), alter.database, alter.table));
     return required_access;
 }
 

src/Interpreters/InterpreterCreateQuery.cpp

@@ -130,6 +130,7 @@ BlockIO InterpreterCreateQuery::createDatabase(ASTCreateQuery & create)
         auto engine = std::make_shared<ASTFunction>();
         auto storage = std::make_shared<ASTStorage>();
         engine->name = old_style_database ? "Ordinary" : "Atomic";
+        engine->no_empty_args = true;
         storage->set(storage->engine, engine);
         create.set(create.storage, storage);
     }
@@ -600,6 +601,7 @@ void InterpreterCreateQuery::setEngine(ASTCreateQuery & create) const
     {
         auto engine_ast = std::make_shared<ASTFunction>();
         engine_ast->name = "Memory";
+        engine_ast->no_empty_args = true;
         auto storage_ast = std::make_shared<ASTStorage>();
         storage_ast->set(storage_ast->engine, engine_ast);
         create.set(create.storage, storage_ast);

src/Interpreters/MonotonicityCheckVisitor.h

@@ -87,8 +87,7 @@ public:
             return;
 
         /// TODO: monotonicity for functions of several arguments
-        auto arguments = ast_function.arguments;
+        if (!ast_function.arguments || ast_function.arguments->children.size() != 1)
-        if (arguments->children.size() != 1)
         {
             data.reject();
             return;

src/Interpreters/MutationsInterpreter.cpp

@@ -442,10 +442,10 @@ ASTPtr MutationsInterpreter::prepare(bool dry_run)
                 auto type_literal = std::make_shared<ASTLiteral>(columns_desc.getPhysical(column).type->getName());
 
                 const auto & update_expr = kv.second;
-                auto updated_column = makeASTFunction("CAST",
+                auto updated_column = makeASTFunction("cast",
                     makeASTFunction("if",
                         getPartitionAndPredicateExpressionForMutationCommand(command),
-                        makeASTFunction("CAST",
+                        makeASTFunction("cast",
                             update_expr->clone(),
                             type_literal),
                         std::make_shared<ASTIdentifier>(column)),

src/Interpreters/MySQL/InterpretersMySQLDDLQuery.cpp

@@ -478,7 +478,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
     auto rewritten_rename_query = std::make_shared<ASTRenameQuery>();
     rewritten_alter_query->database = mapped_to_database;
     rewritten_alter_query->table = alter_query.table;
-    rewritten_alter_query->set(rewritten_alter_query->command_list, std::make_shared<ASTAlterCommandList>());
+    rewritten_alter_query->set(rewritten_alter_query->command_list, std::make_shared<ASTExpressionList>());
 
     String default_after_column;
     for (const auto & command_query : alter_query.command_list->children)
@@ -542,7 +542,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
                 }
 
                 rewritten_command->children.push_back(rewritten_command->col_decl);
-                rewritten_alter_query->command_list->add(rewritten_command);
+                rewritten_alter_query->command_list->children.push_back(rewritten_command);
             }
         }
         else if (alter_command->type == MySQLParser::ASTAlterCommand::DROP_COLUMN)
@@ -550,7 +550,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
             auto rewritten_command = std::make_shared<ASTAlterCommand>();
             rewritten_command->type = ASTAlterCommand::DROP_COLUMN;
             rewritten_command->column = std::make_shared<ASTIdentifier>(alter_command->column_name);
-            rewritten_alter_query->command_list->add(rewritten_command);
+            rewritten_alter_query->command_list->children.push_back(rewritten_command);
         }
         else if (alter_command->type == MySQLParser::ASTAlterCommand::RENAME_COLUMN)
         {
@@ -561,7 +561,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
                 rewritten_command->type = ASTAlterCommand::RENAME_COLUMN;
                 rewritten_command->column = std::make_shared<ASTIdentifier>(alter_command->old_name);
                 rewritten_command->rename_to = std::make_shared<ASTIdentifier>(alter_command->column_name);
-                rewritten_alter_query->command_list->add(rewritten_command);
+                rewritten_alter_query->command_list->children.push_back(rewritten_command);
             }
         }
         else if (alter_command->type == MySQLParser::ASTAlterCommand::MODIFY_COLUMN)
@@ -590,7 +590,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
                     rewritten_command->children.push_back(rewritten_command->column);
                 }
 
-                rewritten_alter_query->command_list->add(rewritten_command);
+                rewritten_alter_query->command_list->children.push_back(rewritten_command);
             }
 
             if (!alter_command->old_name.empty() && alter_command->old_name != new_column_name)
@@ -599,7 +599,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
                 rewritten_command->type = ASTAlterCommand::RENAME_COLUMN;
                 rewritten_command->column = std::make_shared<ASTIdentifier>(alter_command->old_name);
                 rewritten_command->rename_to = std::make_shared<ASTIdentifier>(new_column_name);
-                rewritten_alter_query->command_list->add(rewritten_command);
+                rewritten_alter_query->command_list->children.push_back(rewritten_command);
             }
         }
         else if (alter_command->type == MySQLParser::ASTAlterCommand::RENAME_TABLE)
@@ -624,7 +624,7 @@ ASTs InterpreterAlterImpl::getRewrittenQueries(
     ASTs rewritten_queries;
 
     /// Order is very important. We always execute alter first and then execute rename
-    if (!rewritten_alter_query->command_list->commands.empty())
+    if (!rewritten_alter_query->command_list->children.empty())
         rewritten_queries.push_back(rewritten_alter_query);
 
     if (!rewritten_rename_query->elements.empty())

src/Interpreters/OptimizeIfWithConstantConditionVisitor.cpp

@@ -29,7 +29,7 @@ static bool tryExtractConstValueFromCondition(const ASTPtr & condition, bool & v
     /// cast of numeric constant in condition to UInt8
     if (const auto * function = condition->as<ASTFunction>())
     {
-        if (function->name == "CAST")
+        if (function->name == "cast")
         {
             if (const auto * expr_list = function->arguments->as<ASTExpressionList>())
             {
@@ -64,13 +64,17 @@ void OptimizeIfWithConstantConditionVisitor::visit(ASTPtr & current_ast)
             continue;
         }
 
+        if (!function_node->arguments)
+            throw Exception("Wrong number of arguments for function 'if' (0 instead of 3)", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
+
+        if (function_node->arguments->children.size() != 3)
+            throw Exception(
+                "Wrong number of arguments for function 'if' (" + toString(function_node->arguments->children.size()) + " instead of 3)",
+                ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
+
         visit(function_node->arguments);
         const auto * args = function_node->arguments->as<ASTExpressionList>();
 
-        if (args->children.size() != 3)
-            throw Exception("Wrong number of arguments for function 'if' (" + toString(args->children.size()) + " instead of 3)",
-                            ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
-
         ASTPtr condition_expr = args->children[0];
         ASTPtr then_expr = args->children[1];
         ASTPtr else_expr = args->children[2];

src/Interpreters/QueryNormalizer.cpp

@@ -164,6 +164,8 @@ void QueryNormalizer::visitChildren(const ASTPtr & node, Data & data)
         if (func_node->name == "lambda")
             first_pos = 1;
 
+        if (func_node->arguments)
+        {
             auto & func_children = func_node->arguments->children;
 
             for (size_t i = first_pos; i < func_children.size(); ++i)
@@ -174,6 +176,7 @@ void QueryNormalizer::visitChildren(const ASTPtr & node, Data & data)
                     visit(child, data);
             }
         }
+    }
     else if (!node->as<ASTSelectQuery>())
     {
         for (auto & child : node->children)

src/Interpreters/RemoveInjectiveFunctionsVisitor.cpp

@@ -22,7 +22,7 @@ static bool removeInjectiveFunction(ASTPtr & ast, const Context & context, const
     if (!func)
         return false;
 
-    if (func->arguments->children.size() != 1)
+    if (!func->arguments || func->arguments->children.size() != 1)
         return false;
 
     if (!function_factory.get(func->name, context)->isInjective({}))

src/Interpreters/RewriteAnyFunctionVisitor.cpp

@@ -62,7 +62,7 @@ void RewriteAnyFunctionMatcher::visit(ASTPtr & ast, Data & data)
 
 void RewriteAnyFunctionMatcher::visit(const ASTFunction & func, ASTPtr & ast, Data & data)
 {
-    if (func.arguments->children.empty() || !func.arguments->children[0])
+    if (!func.arguments || func.arguments->children.empty() || !func.arguments->children[0])
         return;
 
     if (func.name != "any" && func.name != "anyLast")

src/Interpreters/StorageID.h

@@ -28,6 +28,7 @@ class ASTQueryWithTableAndOutput;
 class ASTIdentifier;
 class Context;
 
+// TODO(ilezhankin): refactor and merge |ASTTableIdentifier|
 struct StorageID
 {
     String database_name;

src/Interpreters/TranslateQualifiedNamesVisitor.cpp

@@ -126,6 +126,8 @@ void TranslateQualifiedNamesMatcher::visit(ASTFunction & node, const ASTPtr &, D
 {
     ASTPtr & func_arguments = node.arguments;
 
+    if (!func_arguments) return;
+
     String func_name_lowercase = Poco::toLower(node.name);
     if (func_name_lowercase == "count" &&
         func_arguments->children.size() == 1 &&

src/Interpreters/TreeRewriter.cpp

@@ -380,6 +380,7 @@ std::vector<const ASTFunction *> getAggregates(ASTPtr & query, const ASTSelectQu
 
     /// There can not be other aggregate functions within the aggregate functions.
     for (const ASTFunction * node : data.aggregates)
+        if (node->arguments)
             for (auto & arg : node->arguments->children)
                 assertNoAggregates(arg, "inside another aggregate function");
     return data.aggregates;

src/Interpreters/addTypeConversionToAST.cpp

@@ -11,7 +11,7 @@ namespace DB
 
 ASTPtr addTypeConversionToAST(ASTPtr && ast, const String & type_name)
 {
-    auto func = makeASTFunction("CAST", ast, std::make_shared<ASTLiteral>(type_name));
+    auto func = makeASTFunction("cast", ast, std::make_shared<ASTLiteral>(type_name));
 
     if (ASTWithAlias * ast_with_alias = dynamic_cast<ASTWithAlias *>(ast.get()))
     {

src/Interpreters/executeQuery.cpp

@@ -15,18 +15,23 @@
 #include <DataStreams/InputStreamFromASTInsertQuery.h>
 #include <DataStreams/CountingBlockOutputStream.h>
 
+#include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTInsertQuery.h>
+#include <Parsers/ASTLiteral.h>
 #include <Parsers/ASTSelectQuery.h>
 #include <Parsers/ASTSelectWithUnionQuery.h>
 #include <Parsers/ASTShowProcesslistQuery.h>
-#include <Parsers/ASTIdentifier.h>
-#include <Parsers/ASTLiteral.h>
-#include <Parsers/ParserQuery.h>
-#include <Parsers/parseQuery.h>
-#include <Parsers/queryToString.h>
 #include <Parsers/ASTWatchQuery.h>
 #include <Parsers/Lexer.h>
 
+#if !defined(ARCADIA_BUILD)
+#    include <Parsers/New/parseQuery.h>  // Y_IGNORE
+#endif
+
+#include <Parsers/parseQuery.h>
+#include <Parsers/ParserQuery.h>
+#include <Parsers/queryToString.h>
+
 #include <Storages/StorageInput.h>
 
 #include <Access/EnabledQuota.h>
@@ -147,10 +152,11 @@ static void logQuery(const String & query, const Context & context, bool interna
         const auto & initial_query_id = client_info.initial_query_id;
         const auto & current_user = client_info.current_user;
 
-        LOG_DEBUG(&Poco::Logger::get("executeQuery"), "(from {}{}{}) {}",
+        LOG_DEBUG(&Poco::Logger::get("executeQuery"), "(from {}{}{}, using {} parser) {}",
             client_info.current_address.toString(),
             (current_user != "default" ? ", user: " + current_user : ""),
             (!initial_query_id.empty() && current_query_id != initial_query_id ? ", initial_query_id: " + initial_query_id : std::string()),
+            (context.getSettingsRef().use_antlr_parser ? "new" : "old"),
             joinLines(query));
 
         if (client_info.client_trace_context.trace_id)
@@ -321,19 +327,33 @@ static std::tuple<ASTPtr, BlockIO> executeQueryImpl(
 
     const Settings & settings = context.getSettingsRef();
 
-    ParserQuery parser(end);
     ASTPtr ast;
     const char * query_end;
 
     /// Don't limit the size of internal queries.
     size_t max_query_size = 0;
-    if (!internal)
+    if (!internal) max_query_size = settings.max_query_size;
-        max_query_size = settings.max_query_size;
 
     try
     {
-        /// TODO Parser should fail early when max_query_size limit is reached.
+#if !defined(ARCADIA_BUILD)
+        if (settings.use_antlr_parser)
+        {
+            ast = parseQuery(begin, end, max_query_size, settings.max_parser_depth);
+        }
+        else
+        {
+            ParserQuery parser(end);
+
+            /// TODO: parser should fail early when max_query_size limit is reached.
             ast = parseQuery(parser, begin, end, "", max_query_size, settings.max_parser_depth);
+        }
+#else
+        ParserQuery parser(end);
+
+        /// TODO: parser should fail early when max_query_size limit is reached.
+        ast = parseQuery(parser, begin, end, "", max_query_size, settings.max_parser_depth);
+#endif
 
         /// Interpret SETTINGS clauses as early as possible (before invoking the corresponding interpreter),
         /// to allow settings to take effect.
@@ -874,7 +894,7 @@ void executeQuery(
         end = istr.buffer().end();
         istr.position() += end - begin;
         /// Actually we don't know will query has additional data or not.
-        /// But we can't check istr.eof(), because begin and end pointers will became invalid
+        /// But we can't check istr.eof(), because begin and end pointers will become invalid
         may_have_tail = true;
     }
     else

src/Interpreters/inplaceBlockConversions.cpp

@@ -43,7 +43,7 @@ void addDefaultRequiredExpressionsRecursively(Block & block, const String & requ
         RequiredSourceColumnsVisitor(columns_context).visit(column_default_expr);
         NameSet required_columns_names = columns_context.requiredColumns();
 
-        auto cast_func = makeASTFunction("CAST", column_default_expr, std::make_shared<ASTLiteral>(columns.get(required_column).type->getName()));
+        auto cast_func = makeASTFunction("cast", column_default_expr, std::make_shared<ASTLiteral>(columns.get(required_column).type->getName()));
         default_expr_list_accum->children.emplace_back(setAlias(cast_func, required_column));
         added_columns.emplace(required_column);
 
@@ -79,7 +79,7 @@ ASTPtr convertRequiredExpressions(Block & block, const NamesAndTypesList & requi
             continue;
 
         auto cast_func = makeASTFunction(
-            "CAST", std::make_shared<ASTIdentifier>(required_column.name), std::make_shared<ASTLiteral>(required_column.type->getName()));
+            "cast", std::make_shared<ASTIdentifier>(required_column.name), std::make_shared<ASTLiteral>(required_column.type->getName()));
 
         conversion_expr_list->children.emplace_back(setAlias(cast_func, required_column.name));
 

src/Parsers/ASTAlterQuery.cpp

@@ -345,30 +345,6 @@ void ASTAlterCommand::formatImpl(
 }
 
 
-ASTPtr ASTAlterCommandList::clone() const
-{
-    auto res = std::make_shared<ASTAlterCommandList>();
-    for (ASTAlterCommand * command : commands)
-        res->add(command->clone());
-    return res;
-}
-
-void ASTAlterCommandList::formatImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const
-{
-    std::string indent_str = settings.one_line ? "" : std::string(4 * frame.indent, ' ');
-
-    for (size_t i = 0; i < commands.size(); ++i)
-    {
-        static_cast<IAST *>(commands[i])->formatImpl(settings, state, frame);
-
-        std::string comma = (i < (commands.size() - 1)) ? "," : "";
-        settings.ostr << (settings.hilite ? hilite_keyword : "") << comma << (settings.hilite ? hilite_none : "");
-
-        settings.ostr << settings.nl_or_ws;
-    }
-}
-
-
 /** Get the text that identifies this element. */
 String ASTAlterQuery::getID(char delim) const
 {

src/Parsers/ASTAlterQuery.h

@@ -1,9 +1,10 @@
 #pragma once
 
-#include <Parsers/IAST.h>
+#include <Parsers/ASTExpressionList.h>
-#include <Parsers/ASTQueryWithTableAndOutput.h>
 #include <Parsers/ASTQueryWithOnCluster.h>
+#include <Parsers/ASTQueryWithTableAndOutput.h>
 #include <Parsers/ASTTTLElement.h>
+#include <Parsers/IAST.h>
 
 
 namespace DB
@@ -179,31 +180,12 @@ protected:
     void formatImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
 };
 
-class ASTAlterCommandList : public IAST
-{
-public:
-    std::vector<ASTAlterCommand *> commands;
-
-    void add(const ASTPtr & command)
-    {
-        commands.push_back(command->as<ASTAlterCommand>());
-        children.push_back(command);
-    }
-
-    String getID(char) const override { return "AlterCommandList"; }
-
-    ASTPtr clone() const override;
-
-protected:
-    void formatImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
-};
-
 class ASTAlterQuery : public ASTQueryWithTableAndOutput, public ASTQueryWithOnCluster
 {
 public:
     bool is_live_view{false}; /// true for ALTER LIVE VIEW
 
-    ASTAlterCommandList * command_list = nullptr;
+    ASTExpressionList * command_list = nullptr;
 
     String getID(char) const override;
 

src/Parsers/ASTCreateQuery.h

@@ -4,10 +4,10 @@
 #include <Parsers/ASTQueryWithOnCluster.h>
 #include <Parsers/ASTDictionary.h>
 #include <Parsers/ASTDictionaryAttributeDeclaration.h>
+#include <Parsers/ASTIdentifier.h>
 #include <Parsers/ASTSelectWithUnionQuery.h>
 #include <Interpreters/StorageID.h>
 
-
 namespace DB
 {
 

src/Parsers/ASTDictionary.cpp

@@ -65,7 +65,7 @@ ASTPtr ASTDictionaryLayout::clone() const
 {
     auto res = std::make_shared<ASTDictionaryLayout>();
     res->layout_type = layout_type;
-    res->set(res->parameters, parameters->clone());
+    if (parameters) res->set(res->parameters, parameters->clone());
     res->has_brackets = has_brackets;
     return res;
 }
@@ -86,7 +86,7 @@ void ASTDictionaryLayout::formatImpl(const FormatSettings & settings,
     if (has_brackets)
         settings.ostr << "(";
 
-    parameters->formatImpl(settings, state, frame);
+    if (parameters) parameters->formatImpl(settings, state, frame);
 
     if (has_brackets)
         settings.ostr << ")";

src/Parsers/ASTFunction.cpp

@@ -29,6 +29,7 @@ void ASTFunction::appendColumnNameImpl(WriteBuffer & ostr) const
     }
 
     writeChar('(', ostr);
+    if (arguments)
         for (auto it = arguments->children.begin(); it != arguments->children.end(); ++it)
         {
             if (it != arguments->children.begin())
@@ -64,6 +65,35 @@ void ASTFunction::updateTreeHashImpl(SipHash & hash_state) const
 }
 
 
+ASTPtr ASTFunction::toLiteral() const
+{
+    if (!arguments) return {};
+
+    if (name == "array")
+    {
+        Array array;
+
+        for (const auto & arg : arguments->children)
+        {
+            if (auto * literal = arg->as<ASTLiteral>())
+                array.push_back(literal->value);
+            else if (auto * func = arg->as<ASTFunction>())
+            {
+                if (auto func_literal = func->toLiteral())
+                    array.push_back(func_literal->as<ASTLiteral>()->value);
+            }
+            else
+                /// Some of the Array arguments is not literal
+                return {};
+        }
+
+        return std::make_shared<ASTLiteral>(array);
+    }
+
+    return {};
+}
+
+
 /** A special hack. If it's [I]LIKE or NOT [I]LIKE expression and the right hand side is a string literal,
   *  we will highlight unescaped metacharacters % and _ in string literal for convenience.
   * Motivation: most people are unaware that _ is a metacharacter and forgot to properly escape it with two backslashes.
@@ -378,12 +408,14 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
             settings.ostr << (settings.hilite ? hilite_function : "") << ')';
         }
 
-        if (arguments)
+        if ((arguments && !arguments->children.empty()) || !no_empty_args)
-        {
             settings.ostr << '(' << (settings.hilite ? hilite_none : "");
 
+        if (arguments)
+        {
             bool special_hilite_regexp = settings.hilite
-                && (name == "match" || name == "extract" || name == "extractAll" || name == "replaceRegexpOne" || name == "replaceRegexpAll");
+                && (name == "match" || name == "extract" || name == "extractAll" || name == "replaceRegexpOne"
+                    || name == "replaceRegexpAll");
 
             for (size_t i = 0, size = arguments->children.size(); i < size; ++i)
             {
@@ -397,10 +429,11 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
                 if (!special_hilite)
                     arguments->children[i]->formatImpl(settings, state, nested_dont_need_parens);
             }
-
-            settings.ostr << (settings.hilite ? hilite_function : "") << ')';
         }
 
+        if ((arguments && !arguments->children.empty()) || !no_empty_args)
+            settings.ostr << (settings.hilite ? hilite_function : "") << ')';
+
         settings.ostr << (settings.hilite ? hilite_none : "");
     }
 }

src/Parsers/ASTFunction.h

@@ -18,7 +18,9 @@ public:
     /// parameters - for parametric aggregate function. Example: quantile(0.9)(x) - what in first parens are 'parameters'.
     ASTPtr parameters;
 
-public:
+    /// do not print empty parentheses if there are no args - compatibility with new AST for data types and engine names.
+    bool no_empty_args = false;
+
     /** Get text identifying the AST node. */
     String getID(char delim) const override;
 
@@ -28,6 +30,8 @@ public:
 
     ASTSelectWithUnionQuery * tryGetQueryArgument() const;
 
+    ASTPtr toLiteral() const;  // Try to convert functions like Array or Tuple to a literal form.
+
 protected:
     void formatImplWithoutAlias(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
     void appendColumnNameImpl(WriteBuffer & ostr) const override;

src/Parsers/ASTIdentifier.h

@@ -73,7 +73,6 @@ private:
     void resetFullName();
 };
 
-
 /// ASTIdentifier Helpers: hide casts and semantic.
 
 ASTPtr createTableIdentifier(const String & database_name, const String & table_name);

src/Parsers/ASTLiteral.h

@@ -1,20 +1,23 @@
 #pragma once
 
 #include <Core/Field.h>
-#include <Common/FieldVisitors.h>
 #include <Parsers/ASTWithAlias.h>
 #include <Parsers/TokenIterator.h>
+#include <Common/FieldVisitors.h>
+
 #include <optional>
 
 
 namespace DB
 {
 
-/** Literal (atomic) - number, string, NULL
+/// Literal (atomic) - number, string, NULL
-  */
 class ASTLiteral : public ASTWithAlias
 {
 public:
+    explicit ASTLiteral(Field && value_) : value(value_) {}
+    explicit ASTLiteral(const Field & value_) : value(value_) {}
+
     Field value;
 
     /// For ConstantExpressionTemplate
@@ -30,11 +33,6 @@ public:
      */
     String unique_column_name;
 
-
-public:
-    ASTLiteral(Field && value_) : value(value_) {}
-    ASTLiteral(const Field & value_) : value(value_) {}
-
     /** Get the text that identifies this element. */
     String getID(char delim) const override { return "Literal" + (delim + applyVisitor(FieldVisitorDump(), value)); }
 

src/Parsers/ASTOrderByElement.h

@@ -23,20 +23,6 @@ public:
     ASTPtr fill_to;
     ASTPtr fill_step;
 
-    ASTOrderByElement(
-        const int direction_, const int nulls_direction_, const bool nulls_direction_was_explicitly_specified_,
-        ASTPtr & collation_, const bool with_fill_, ASTPtr & fill_from_, ASTPtr & fill_to_, ASTPtr & fill_step_)
-        : direction(direction_)
-        , nulls_direction(nulls_direction_)
-        , nulls_direction_was_explicitly_specified(nulls_direction_was_explicitly_specified_)
-        , collation(collation_)
-        , with_fill(with_fill_)
-        , fill_from(fill_from_)
-        , fill_to(fill_to_)
-        , fill_step(fill_step_)
-    {
-    }
-
     String getID(char) const override { return "OrderByElement"; }
 
     ASTPtr clone() const override

src/Parsers/ASTSampleRatio.h

@@ -26,7 +26,7 @@ public:
 
     Rational ratio;
 
-    ASTSampleRatio(Rational & ratio_) : ratio(ratio_) {}
+    explicit ASTSampleRatio(const Rational & ratio_) : ratio(ratio_) {}
 
     String getID(char delim) const override { return "SampleRatio" + (delim + toString(ratio)); }
 

src/Parsers/ASTTablesInSelectQuery.h

@@ -30,7 +30,7 @@ namespace DB
   *  , (comma)
   *
   * In all kinds except cross and comma, there are join condition in one of following forms:
-  *  USING (a, b c)
+  *  USING (a, b, c)
   *  USING a, b, c
   *  ON expr...
   *

src/Parsers/ExpressionElementParsers.cpp

@@ -441,7 +441,7 @@ bool ParserCastExpression::parseImpl(Pos & pos, ASTPtr & node, Expected & expect
         expr_list_args->children.push_back(std::move(type_literal));
 
         auto func_node = std::make_shared<ASTFunction>();
-        func_node->name = "CAST";
+        func_node->name = "cast";
         func_node->arguments = std::move(expr_list_args);
         func_node->children.push_back(func_node->arguments);
 
@@ -1705,12 +1705,21 @@ bool ParserOrderByElement::parseImpl(Pos & pos, ASTPtr & node, Expected & expect
             return false;
     }
 
-    node = std::make_shared<ASTOrderByElement>(
+    auto elem = std::make_shared<ASTOrderByElement>();
-            direction, nulls_direction, nulls_direction_was_explicitly_specified, locale_node,
+
-            has_with_fill, fill_from, fill_to, fill_step);
+    elem->direction = direction;
-    node->children.push_back(expr_elem);
+    elem->nulls_direction = nulls_direction;
+    elem->nulls_direction_was_explicitly_specified = nulls_direction_was_explicitly_specified;
+    elem->collation = locale_node;
+    elem->with_fill = has_with_fill;
+    elem->fill_from = fill_from;
+    elem->fill_to = fill_to;
+    elem->fill_step = fill_step;
+    elem->children.push_back(expr_elem);
     if (locale_node)
-        node->children.push_back(locale_node);
+        elem->children.push_back(locale_node);
+
+    node = elem;
 
     return true;
 }
@@ -1887,13 +1896,18 @@ bool ParserIdentifierWithOptionalParameters::parseImpl(Pos & pos, ASTPtr & node,
     ParserIdentifierWithParameters parametric;
 
     if (parametric.parse(pos, node, expected))
+    {
+        auto * func = node->as<ASTFunction>();
+        func->no_empty_args = true;
         return true;
+    }
 
     ASTPtr ident;
     if (non_parametric.parse(pos, ident, expected))
     {
         auto func = std::make_shared<ASTFunction>();
         tryGetIdentifierNameInto(ident, func->name);
+        func->no_empty_args = true;
         node = func;
         return true;
     }

src/Parsers/IAST.cpp

@@ -13,6 +13,7 @@ namespace ErrorCodes
     extern const int TOO_BIG_AST;
     extern const int TOO_DEEP_AST;
     extern const int BAD_ARGUMENTS;
+    extern const int UNKNOWN_ELEMENT_IN_AST;
 }
 
 
@@ -154,7 +155,10 @@ void IAST::dumpTree(WriteBuffer & ostr, size_t indent) const
     writePointerHex(this, ostr);
     writeChar('\n', ostr);
     for (const auto & child : children)
+    {
+        if (!child) throw Exception("Can't dump nullptr child", ErrorCodes::UNKNOWN_ELEMENT_IN_AST);
         child->dumpTree(ostr, indent + 1);
     }
+}
 
 }

src/Parsers/New/AST/AlterTableQuery.cpp

@@ -0,0 +1,687 @@
+#include <Parsers/New/AST/AlterTableQuery.h>
+
+#include <Interpreters/StorageID.h>
+#include <Parsers/ASTAlterQuery.h>
+#include <Parsers/ASTAssignment.h>
+#include <Parsers/ASTColumnDeclaration.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTPartition.h>
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/TableElementExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+AssignmentExpr::AssignmentExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExpr> expr) : INode{identifier, expr}
+{
+}
+
+ASTPtr AssignmentExpr::convertToOld() const
+{
+    auto expr = std::make_shared<ASTAssignment>();
+
+    expr->column_name = get(IDENTIFIER)->convertToOld()->getColumnName();
+    expr->children.push_back(get(EXPR)->convertToOld());
+
+    return expr;
+}
+
+PartitionClause::PartitionClause(PtrTo<Literal> id) : PartitionClause(ClauseType::ID, {id})
+{
+}
+
+PartitionClause::PartitionClause(PtrTo<List<Literal>> list) : PartitionClause(ClauseType::LIST, {list})
+{
+}
+
+PartitionClause::PartitionClause(ClauseType type, PtrList exprs) : INode(exprs), clause_type(type)
+{
+}
+
+ASTPtr PartitionClause::convertToOld() const
+{
+    auto partition = std::make_shared<ASTPartition>();
+
+    switch(clause_type)
+    {
+        case ClauseType::ID:
+            partition->id = get<StringLiteral>(ID)->as<String>();
+            break;
+        case ClauseType::LIST:
+            {
+                auto tuple = std::make_shared<ASTFunction>();
+
+                tuple->name = "tuple";
+                tuple->arguments = std::make_shared<ASTExpressionList>();
+                for (const auto & child : get(LIST)->as<List<Literal> &>())
+                    tuple->arguments->children.push_back(child->convertToOld());
+                tuple->children.push_back(tuple->arguments);
+
+                partition->value = tuple;
+                partition->children.push_back(partition->value);
+                partition->fields_count = get<List<Literal>>(LIST)->size();
+                partition->fields_str = get(LIST)->toString();
+            }
+            break;
+    }
+
+    return partition;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createAddColumn(bool if_not_exists, PtrTo<TableElementExpr> element, PtrTo<Identifier> after)
+{
+    assert(element->getType() == TableElementExpr::ExprType::COLUMN);
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::ADD_COLUMN, {element, after}));
+    query->if_not_exists = if_not_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createAddIndex(bool if_not_exists, PtrTo<TableElementExpr> element, PtrTo<Identifier> after)
+{
+    assert(element->getType() == TableElementExpr::ExprType::INDEX);
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::ADD_INDEX, {element, after}));
+    query->if_not_exists = if_not_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createAttach(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> from)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::ATTACH, {clause, from}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createClear(bool if_exists, PtrTo<Identifier> identifier, PtrTo<PartitionClause> in)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::CLEAR, {identifier, in}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createCodec(bool if_exists, PtrTo<Identifier> identifier, PtrTo<CodecExpr> codec)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::CODEC, {identifier, codec}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createComment(bool if_exists, PtrTo<Identifier> identifier, PtrTo<StringLiteral> comment)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::COMMENT, {identifier, comment}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createDelete(PtrTo<ColumnExpr> expr)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::DELETE, {expr}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createDetach(PtrTo<PartitionClause> clause)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::DETACH, {clause}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createDropColumn(bool if_exists, PtrTo<Identifier> identifier)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::DROP_COLUMN, {identifier}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createDropIndex(bool if_exists, PtrTo<Identifier> identifier)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::DROP_INDEX, {identifier}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createDropPartition(PtrTo<PartitionClause> clause)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::DROP_PARTITION, {clause}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createFreezePartition(PtrTo<PartitionClause> clause)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::FREEZE_PARTITION, {clause}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createModify(bool if_exists, PtrTo<TableElementExpr> element)
+{
+    // TODO: assert(element->getType() == TableElementExpr::ExprType::COLUMN);
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::MODIFY, {element}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createMovePartitionToDisk(PtrTo<PartitionClause> clause, PtrTo<StringLiteral> literal)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::MOVE_PARTITION_TO_DISK, {clause, literal}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createMovePartitionToTable(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> identifier)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::MOVE_PARTITION_TO_TABLE, {clause, identifier}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createMovePartitionToVolume(PtrTo<PartitionClause> clause, PtrTo<StringLiteral> literal)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::MOVE_PARTITION_TO_VOLUME, {clause, literal}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createOrderBy(PtrTo<ColumnExpr> expr)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::ORDER_BY, {expr}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createRemove(bool if_exists, PtrTo<Identifier> identifier, TableColumnPropertyType type)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::REMOVE, {identifier}));
+    query->if_exists = if_exists;
+    query->property_type = type;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createRemoveTTL()
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::REMOVE_TTL, {}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createRename(bool if_exists, PtrTo<Identifier> identifier, PtrTo<Identifier> to)
+{
+    PtrTo<AlterTableClause> query(new AlterTableClause(ClauseType::RENAME, {identifier, to}));
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createReplace(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> from)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::REPLACE, {clause, from}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createTTL(PtrTo<TTLClause> clause)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::TTL, {clause}));
+}
+
+// static
+PtrTo<AlterTableClause> AlterTableClause::createUpdate(PtrTo<AssignmentExprList> list, PtrTo<WhereClause> where)
+{
+    return PtrTo<AlterTableClause>(new AlterTableClause(ClauseType::UPDATE, {list, where}));
+}
+
+ASTPtr AlterTableClause::convertToOld() const
+{
+    auto command = std::make_shared<ASTAlterCommand>();
+
+    switch(clause_type)
+    {
+        case ClauseType::ADD_COLUMN:
+            command->type = ASTAlterCommand::ADD_COLUMN;
+            command->if_not_exists = if_not_exists;
+            // TODO: command->first
+            command->col_decl = get(ELEMENT)->convertToOld();
+            if (has(AFTER)) command->column = get(AFTER)->convertToOld();
+            break;
+
+        case ClauseType::ADD_INDEX:
+            command->type = ASTAlterCommand::ADD_INDEX;
+            command->if_not_exists = if_not_exists;
+            command->index_decl = get(ELEMENT)->convertToOld();
+            if (has(AFTER)) command->index = get(AFTER)->convertToOld();
+            break;
+
+        case ClauseType::ATTACH:
+            command->type = ASTAlterCommand::ATTACH_PARTITION;
+            command->partition = get(PARTITION)->convertToOld();
+
+            if (has(FROM))
+            {
+                auto table_id = getTableIdentifier(get(FROM)->convertToOld());
+
+                command->from_database = table_id.database_name;
+                command->from_table = table_id.table_name;
+                command->replace = false;
+                command->type = ASTAlterCommand::REPLACE_PARTITION;
+            }
+            break;
+
+        case ClauseType::CLEAR:
+            command->type = ASTAlterCommand::DROP_COLUMN;
+            command->if_exists = if_exists;
+            command->clear_column = true;
+            command->detach = false;
+            command->column = get(COLUMN)->convertToOld();
+            if (has(IN)) command->partition = get(IN)->convertToOld();
+            break;
+
+        case ClauseType::CODEC:
+            command->type = ASTAlterCommand::MODIFY_COLUMN;
+            command->if_exists = if_exists;
+
+            {
+                auto column = std::make_shared<ASTColumnDeclaration>();
+                column->name = get(COLUMN)->toString();
+                column->codec = get(CODEC)->convertToOld();
+
+                command->col_decl = column;
+            }
+            break;
+
+        case ClauseType::COMMENT:
+            command->type = ASTAlterCommand::COMMENT_COLUMN;
+            command->if_exists = if_exists;
+            command->column = get(COLUMN)->convertToOld();
+            command->comment = get(COMMENT)->convertToOld();
+            break;
+
+        case ClauseType::DELETE:
+            command->type = ASTAlterCommand::DELETE;
+            command->predicate = get(EXPR)->convertToOld();
+            break;
+
+        case ClauseType::DETACH:
+            command->type = ASTAlterCommand::DROP_PARTITION;
+            command->detach = true;
+            command->partition = get(PARTITION)->convertToOld();
+            break;
+
+        case ClauseType::DROP_COLUMN:
+            command->type = ASTAlterCommand::DROP_COLUMN;
+            command->if_exists = if_exists;
+            command->detach = false;
+            command->column = get(COLUMN)->convertToOld();
+            break;
+
+        case ClauseType::DROP_INDEX:
+            command->type = ASTAlterCommand::DROP_INDEX;
+            command->if_exists = if_exists;
+            command->detach = false;
+            command->index = get(COLUMN)->convertToOld();
+            break;
+
+        case ClauseType::DROP_PARTITION:
+            command->type = ASTAlterCommand::DROP_PARTITION;
+            command->partition = get(PARTITION)->convertToOld();
+            break;
+
+        case ClauseType::FREEZE_PARTITION:
+            if (has(PARTITION))
+            {
+                command->type = ASTAlterCommand::FREEZE_PARTITION;
+                command->partition = get(PARTITION)->convertToOld();
+            }
+            else
+                command->type = ASTAlterCommand::FREEZE_ALL;
+            break;
+
+        case ClauseType::MODIFY:
+            command->type = ASTAlterCommand::MODIFY_COLUMN;
+            command->if_exists = if_exists;
+            command->col_decl = get(ELEMENT)->convertToOld();
+            break;
+
+        case ClauseType::MOVE_PARTITION_TO_DISK:
+            command->type = ASTAlterCommand::MOVE_PARTITION;
+            command->partition = get(PARTITION)->convertToOld();
+            command->move_destination_type = DataDestinationType::DISK;
+            command->move_destination_name = get(TO)->convertToOld()->as<ASTLiteral>()->value.get<String>();
+            break;
+
+        case ClauseType::MOVE_PARTITION_TO_TABLE:
+            command->type = ASTAlterCommand::MOVE_PARTITION;
+            command->partition = get(PARTITION)->convertToOld();
+            command->move_destination_type = DataDestinationType::TABLE;
+            {
+                auto table_id = getTableIdentifier(get(TO)->convertToOld());
+                command->to_database = table_id.database_name;
+                command->to_table = table_id.table_name;
+            }
+            break;
+
+        case ClauseType::MOVE_PARTITION_TO_VOLUME:
+            command->type = ASTAlterCommand::MOVE_PARTITION;
+            command->partition = get(PARTITION)->convertToOld();
+            command->move_destination_type = DataDestinationType::VOLUME;
+            command->move_destination_name = get(TO)->convertToOld()->as<ASTLiteral>()->value.get<String>();
+            break;
+
+        case ClauseType::REMOVE:
+            command->type = ASTAlterCommand::MODIFY_COLUMN;
+            command->if_exists = if_exists;
+            {
+                auto col_decl = std::make_shared<ASTColumnDeclaration>();
+                col_decl->name = get(ELEMENT)->convertToOld()->getColumnName();
+                command->col_decl = col_decl;
+            }
+            switch(property_type)
+            {
+                case TableColumnPropertyType::ALIAS:
+                    command->remove_property = "ALIAS";
+                    break;
+                case TableColumnPropertyType::CODEC:
+                    command->remove_property = "CODEC";
+                    break;
+                case TableColumnPropertyType::COMMENT:
+                    command->remove_property = "COMMENT";
+                    break;
+                case TableColumnPropertyType::DEFAULT:
+                    command->remove_property = "DEFAULT";
+                    break;
+                case TableColumnPropertyType::MATERIALIZED:
+                    command->remove_property = "MATERIALIZED";
+                    break;
+                case TableColumnPropertyType::TTL:
+                    command->remove_property = "TTL";
+                    break;
+            }
+            break;
+
+        case ClauseType::REMOVE_TTL:
+            command->type = ASTAlterCommand::REMOVE_TTL;
+            break;
+
+        case ClauseType::RENAME:
+            command->type = ASTAlterCommand::RENAME_COLUMN;
+            command->column = get(COLUMN)->convertToOld();
+            command->rename_to = get(TO)->convertToOld();
+            break;
+
+        case ClauseType::ORDER_BY:
+            command->type = ASTAlterCommand::MODIFY_ORDER_BY;
+            command->order_by = get(EXPR)->convertToOld();
+            break;
+
+        case ClauseType::REPLACE:
+            command->type = ASTAlterCommand::REPLACE_PARTITION;
+            command->replace = true;
+            command->partition = get(PARTITION)->convertToOld();
+            {
+                auto table_id = getTableIdentifier(get(FROM)->convertToOld());
+                command->from_database = table_id.database_name;
+                command->from_table = table_id.table_name;
+            }
+            break;
+
+        case ClauseType::TTL:
+            command->type = ASTAlterCommand::MODIFY_TTL;
+            command->ttl = get(CLAUSE)->convertToOld();
+            break;
+
+        case ClauseType::UPDATE:
+            command->type = ASTAlterCommand::UPDATE;
+            command->update_assignments = get(ASSIGNMENTS)->convertToOld();
+            command->predicate = get(WHERE)->convertToOld();
+            break;
+    }
+
+    if (command->col_decl)
+        command->children.push_back(command->col_decl);
+    if (command->column)
+        command->children.push_back(command->column);
+    if (command->partition)
+        command->children.push_back(command->partition);
+    if (command->order_by)
+        command->children.push_back(command->order_by);
+    if (command->sample_by)
+        command->children.push_back(command->sample_by);
+    if (command->predicate)
+        command->children.push_back(command->predicate);
+    if (command->update_assignments)
+        command->children.push_back(command->update_assignments);
+    if (command->values)
+        command->children.push_back(command->values);
+    if (command->comment)
+        command->children.push_back(command->comment);
+    if (command->ttl)
+        command->children.push_back(command->ttl);
+    if (command->settings_changes)
+        command->children.push_back(command->settings_changes);
+
+    return command;
+}
+
+AlterTableClause::AlterTableClause(ClauseType type, PtrList exprs) : INode(exprs), clause_type(type)
+{
+}
+
+AlterTableQuery::AlterTableQuery(PtrTo<ClusterClause> cluster, PtrTo<TableIdentifier> identifier, PtrTo<List<AlterTableClause>> clauses)
+    : DDLQuery(cluster, {identifier, clauses})
+{
+}
+
+ASTPtr AlterTableQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTAlterQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(TABLE)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+    }
+
+    query->cluster = cluster_name;
+
+    query->set(query->command_list, get(CLAUSES)->convertToOld());
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseAddColumn(ClickHouseParser::AlterTableClauseAddColumnContext * ctx)
+{
+    auto after = ctx->AFTER() ? visit(ctx->nestedIdentifier()).as<PtrTo<Identifier>>() : nullptr;
+    return AlterTableClause::createAddColumn(!!ctx->IF(), visit(ctx->tableColumnDfnt()), after);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseAddIndex(ClickHouseParser::AlterTableClauseAddIndexContext * ctx)
+{
+    auto after = ctx->AFTER() ? visit(ctx->nestedIdentifier()).as<PtrTo<Identifier>>() : nullptr;
+    return AlterTableClause::createAddIndex(!!ctx->IF(), visit(ctx->tableIndexDfnt()), after);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseAttach(ClickHouseParser::AlterTableClauseAttachContext *ctx)
+{
+    auto from = ctx->tableIdentifier() ? visit(ctx->tableIdentifier()).as<PtrTo<TableIdentifier>>() : nullptr;
+    return AlterTableClause::createAttach(visit(ctx->partitionClause()), from);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseClear(ClickHouseParser::AlterTableClauseClearContext * ctx)
+{
+    auto partition = ctx->partitionClause() ? visit(ctx->partitionClause()).as<PtrTo<PartitionClause>>() : nullptr;
+    return AlterTableClause::createClear(!!ctx->IF(), visit(ctx->nestedIdentifier()), partition);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseComment(ClickHouseParser::AlterTableClauseCommentContext * ctx)
+{
+    return AlterTableClause::createComment(!!ctx->IF(), visit(ctx->nestedIdentifier()), Literal::createString(ctx->STRING_LITERAL()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseDelete(ClickHouseParser::AlterTableClauseDeleteContext *ctx)
+{
+    return AlterTableClause::createDelete(visit(ctx->columnExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseDetach(ClickHouseParser::AlterTableClauseDetachContext *ctx)
+{
+    return AlterTableClause::createDetach(visit(ctx->partitionClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseDropColumn(ClickHouseParser::AlterTableClauseDropColumnContext * ctx)
+{
+    return AlterTableClause::createDropColumn(!!ctx->IF(), visit(ctx->nestedIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseDropIndex(ClickHouseParser::AlterTableClauseDropIndexContext * ctx)
+{
+    return AlterTableClause::createDropIndex(!!ctx->IF(), visit(ctx->nestedIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseDropPartition(ClickHouseParser::AlterTableClauseDropPartitionContext *ctx)
+{
+    return AlterTableClause::createDropPartition(visit(ctx->partitionClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseFreezePartition(ClickHouseParser::AlterTableClauseFreezePartitionContext *ctx)
+{
+    auto clause = ctx->partitionClause() ? visit(ctx->partitionClause()).as<PtrTo<PartitionClause>>() : nullptr;
+    return AlterTableClause::createFreezePartition(clause);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModify(ClickHouseParser::AlterTableClauseModifyContext * ctx)
+{
+    return AlterTableClause::createModify(!!ctx->IF(), visit(ctx->tableColumnDfnt()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModifyCodec(ClickHouseParser::AlterTableClauseModifyCodecContext * ctx)
+{
+    return AlterTableClause::createCodec(!!ctx->IF(), visit(ctx->nestedIdentifier()), visit(ctx->codecExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModifyComment(ClickHouseParser::AlterTableClauseModifyCommentContext *ctx)
+{
+    return AlterTableClause::createComment(!!ctx->IF(), visit(ctx->nestedIdentifier()), Literal::createString(ctx->STRING_LITERAL()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModifyOrderBy(ClickHouseParser::AlterTableClauseModifyOrderByContext * ctx)
+{
+    return AlterTableClause::createOrderBy(visit(ctx->columnExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModifyRemove(ClickHouseParser::AlterTableClauseModifyRemoveContext *ctx)
+{
+    return AlterTableClause::createRemove(!!ctx->IF(), visit(ctx->nestedIdentifier()), visit(ctx->tableColumnPropertyType()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseModifyTTL(ClickHouseParser::AlterTableClauseModifyTTLContext *ctx)
+{
+    return AlterTableClause::createTTL(visit(ctx->ttlClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseMovePartition(ClickHouseParser::AlterTableClauseMovePartitionContext *ctx)
+{
+    if (ctx->DISK())
+        return AlterTableClause::createMovePartitionToDisk(visit(ctx->partitionClause()), Literal::createString(ctx->STRING_LITERAL()));
+    if (ctx->TABLE())
+        return AlterTableClause::createMovePartitionToTable(visit(ctx->partitionClause()), visit(ctx->tableIdentifier()));
+    if (ctx->VOLUME())
+        return AlterTableClause::createMovePartitionToVolume(visit(ctx->partitionClause()), Literal::createString(ctx->STRING_LITERAL()));
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseRemoveTTL(ClickHouseParser::AlterTableClauseRemoveTTLContext *)
+{
+    return AlterTableClause::createRemoveTTL();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseRename(ClickHouseParser::AlterTableClauseRenameContext *ctx)
+{
+    return AlterTableClause::createRename(!!ctx->IF(), visit(ctx->nestedIdentifier(0)), visit(ctx->nestedIdentifier(1)));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseReplace(ClickHouseParser::AlterTableClauseReplaceContext *ctx)
+{
+    return AlterTableClause::createReplace(visit(ctx->partitionClause()), visit(ctx->tableIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableClauseUpdate(ClickHouseParser::AlterTableClauseUpdateContext *ctx)
+{
+    return AlterTableClause::createUpdate(visit(ctx->assignmentExprList()), visit(ctx->whereClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAlterTableStmt(ClickHouseParser::AlterTableStmtContext * ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto list = std::make_shared<List<AlterTableClause>>();
+    for (auto * clause : ctx->alterTableClause()) list->push(visit(clause));
+    return std::make_shared<AlterTableQuery>(cluster, visit(ctx->tableIdentifier()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAssignmentExpr(ClickHouseParser::AssignmentExprContext *ctx)
+{
+    return std::make_shared<AssignmentExpr>(visit(ctx->nestedIdentifier()), visit(ctx->columnExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitAssignmentExprList(ClickHouseParser::AssignmentExprListContext *ctx)
+{
+    auto list = std::make_shared<AssignmentExprList>();
+    for (auto * expr : ctx->assignmentExpr()) list->push(visit(expr));
+    return list;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitTableColumnPropertyType(ClickHouseParser::TableColumnPropertyTypeContext *ctx)
+{
+    if (ctx->ALIAS()) return TableColumnPropertyType::ALIAS;
+    if (ctx->CODEC()) return TableColumnPropertyType::CODEC;
+    if (ctx->COMMENT()) return TableColumnPropertyType::COMMENT;
+    if (ctx->DEFAULT()) return TableColumnPropertyType::DEFAULT;
+    if (ctx->MATERIALIZED()) return TableColumnPropertyType::MATERIALIZED;
+    if (ctx->TTL()) return TableColumnPropertyType::TTL;
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitPartitionClause(ClickHouseParser::PartitionClauseContext *ctx)
+{
+    if (ctx->STRING_LITERAL())
+        return std::make_shared<PartitionClause>(Literal::createString(ctx->STRING_LITERAL()));
+
+    auto expr = visit(ctx->columnExpr()).as<PtrTo<ColumnExpr>>();
+
+    if (expr->getType() == ColumnExpr::ExprType::LITERAL)
+        return std::make_shared<PartitionClause>(PtrTo<List<Literal>>(new List<Literal>{expr->getLiteral()}));
+
+    if (expr->getType() == ColumnExpr::ExprType::FUNCTION && expr->getFunctionName() == "tuple")
+    {
+        auto list = std::make_shared<List<Literal>>();
+
+        for (auto it = expr->argumentsBegin(); it != expr->argumentsEnd(); ++it)
+        {
+            auto * literal = (*it)->as<ColumnExpr>();
+
+            if (literal->getType() == ColumnExpr::ExprType::LITERAL)
+                list->push(literal->getLiteral());
+            else
+            {
+                // TODO: 'Expected tuple of literals as Partition Expression'.
+            }
+        }
+
+        return std::make_shared<PartitionClause>(list);
+    }
+
+    // TODO: 'Expected tuple of literals as Partition Expression'.
+    __builtin_unreachable();
+}
+
+}

src/Parsers/New/AST/AlterTableQuery.h

@@ -0,0 +1,179 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class AssignmentExpr : public INode
+{
+    public:
+        AssignmentExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExpr> expr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            IDENTIFIER = 0,  // Identifier
+            EXPR = 1,        // ColumnExpr
+        };
+};
+
+enum class TableColumnPropertyType
+{
+    ALIAS,
+    CODEC,
+    COMMENT,
+    DEFAULT,
+    MATERIALIZED,
+    TTL,
+};
+
+class PartitionClause : public INode
+{
+    public:
+        explicit PartitionClause(PtrTo<Literal> id);
+        explicit PartitionClause(PtrTo<List<Literal>> list);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            ID = 0,    // Literal
+            LIST = 0,  // List<Literal>
+        };
+        enum class ClauseType
+        {
+            ID,
+            LIST,
+        };
+
+        const ClauseType clause_type;
+
+        PartitionClause(ClauseType type, PtrList exprs);
+};
+
+class AlterTableClause : public INode
+{
+    public:
+        static PtrTo<AlterTableClause> createAddColumn(bool if_not_exists, PtrTo<TableElementExpr> element, PtrTo<Identifier> after);
+        static PtrTo<AlterTableClause> createAddIndex(bool if_not_exists, PtrTo<TableElementExpr> element, PtrTo<Identifier> after);
+        static PtrTo<AlterTableClause> createAttach(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> from);
+        static PtrTo<AlterTableClause> createClear(bool if_exists, PtrTo<Identifier> identifier, PtrTo<PartitionClause> in);
+        static PtrTo<AlterTableClause> createCodec(bool if_exists, PtrTo<Identifier> identifier, PtrTo<CodecExpr> codec);
+        static PtrTo<AlterTableClause> createComment(bool if_exists, PtrTo<Identifier> identifier, PtrTo<StringLiteral> comment);
+        static PtrTo<AlterTableClause> createDelete(PtrTo<ColumnExpr> expr);
+        static PtrTo<AlterTableClause> createDetach(PtrTo<PartitionClause> clause);
+        static PtrTo<AlterTableClause> createDropColumn(bool if_exists, PtrTo<Identifier> identifier);
+        static PtrTo<AlterTableClause> createDropIndex(bool if_exists, PtrTo<Identifier> identifier);
+        static PtrTo<AlterTableClause> createDropPartition(PtrTo<PartitionClause> clause);
+        static PtrTo<AlterTableClause> createFreezePartition(PtrTo<PartitionClause> clause);
+        static PtrTo<AlterTableClause> createModify(bool if_exists, PtrTo<TableElementExpr> element);
+        static PtrTo<AlterTableClause> createMovePartitionToDisk(PtrTo<PartitionClause> clause, PtrTo<StringLiteral> literal);
+        static PtrTo<AlterTableClause> createMovePartitionToTable(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> identifier);
+        static PtrTo<AlterTableClause> createMovePartitionToVolume(PtrTo<PartitionClause> clause, PtrTo<StringLiteral> literal);
+        static PtrTo<AlterTableClause> createRemove(bool if_exists, PtrTo<Identifier> identifier, TableColumnPropertyType type);
+        static PtrTo<AlterTableClause> createRemoveTTL();
+        static PtrTo<AlterTableClause> createRename(bool if_exists, PtrTo<Identifier> identifier, PtrTo<Identifier> to);
+        static PtrTo<AlterTableClause> createOrderBy(PtrTo<ColumnExpr> expr);
+        static PtrTo<AlterTableClause> createReplace(PtrTo<PartitionClause> clause, PtrTo<TableIdentifier> from);
+        static PtrTo<AlterTableClause> createTTL(PtrTo<TTLClause> clause);
+        static PtrTo<AlterTableClause> createUpdate(PtrTo<AssignmentExprList> list, PtrTo<WhereClause> where);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            // ADD COLUMN or INDEX
+            ELEMENT = 0,  // TableElementExpr
+            AFTER = 1,    // Identifier (optional)
+
+            // ATTACH/REPLACE
+            PARTITION = 0,  // PartitionClause
+            FROM = 1,       // TableIdentifier (optional)
+
+            // CLEAR
+            COLUMN = 0,  // Identifier
+            IN = 1,      // PartitionClause
+
+            // CODEC
+            CODEC = 1,  // CodecExpr
+
+            // COMMENT
+            COMMENT = 1,  // StringLiteral
+
+            // DELETE
+            EXPR = 0,  // ColumnExpr
+
+            // MOVE
+            // TO = 1,  // TableIdentifier or StringLiteral
+
+            // RENAME
+            TO = 1,      // Identifier
+
+            // TTL
+            CLAUSE = 0,  // TTLClause
+
+            // UPDATE
+            ASSIGNMENTS = 0,  // AssignmentExprList
+            WHERE = 1,        // WhereClause
+        };
+
+        enum class ClauseType
+        {
+            ADD_COLUMN,
+            ADD_INDEX,
+            ATTACH,
+            CLEAR,
+            CODEC,
+            COMMENT,
+            DELETE,
+            DETACH,
+            DROP_COLUMN,
+            DROP_INDEX,
+            DROP_PARTITION,
+            FREEZE_PARTITION,
+            MODIFY,
+            MOVE_PARTITION_TO_DISK,
+            MOVE_PARTITION_TO_TABLE,
+            MOVE_PARTITION_TO_VOLUME,
+            ORDER_BY,
+            REMOVE,
+            REMOVE_TTL,
+            RENAME,
+            REPLACE,
+            TTL,
+            UPDATE,
+        };
+
+        const ClauseType clause_type;
+        TableColumnPropertyType property_type = TableColumnPropertyType::ALIAS;  // default value to silence PVS-Studio
+        union
+        {
+            bool if_exists;
+            bool if_not_exists;
+        };
+
+        AlterTableClause(ClauseType type, PtrList exprs);
+};
+
+class AlterTableQuery : public DDLQuery
+{
+    public:
+        AlterTableQuery(PtrTo<ClusterClause> cluster, PtrTo<TableIdentifier> identifier, PtrTo<List<AlterTableClause>> clauses);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            TABLE = 0,    // TableIdentifier
+            CLAUSES = 1,  // List<AlterTableClause>
+        };
+};
+
+}

src/Parsers/New/AST/AttachQuery.cpp

@@ -0,0 +1,57 @@
+#include <Parsers/New/AST/AttachQuery.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<AttachQuery> AttachQuery::createDictionary(PtrTo<ClusterClause> clause, PtrTo<TableIdentifier> identifier)
+{
+    return PtrTo<AttachQuery>(new AttachQuery(clause, QueryType::DICTIONARY, {identifier}));
+}
+
+AttachQuery::AttachQuery(PtrTo<ClusterClause> clause, QueryType type, PtrList exprs) : DDLQuery(clause, exprs), query_type(type)
+{
+}
+
+ASTPtr AttachQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    query->attach = true;
+
+    switch(query_type)
+    {
+        case QueryType::DICTIONARY:
+            query->is_dictionary = true;
+            {
+                auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+                query->database = table_id.database_name;
+                query->table = table_id.table_name;
+            }
+            break;
+    }
+
+    query->cluster = cluster_name;
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitAttachDictionaryStmt(ClickHouseParser::AttachDictionaryStmtContext *ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    return AttachQuery::createDictionary(cluster, visit(ctx->tableIdentifier()));
+}
+
+}

src/Parsers/New/AST/AttachQuery.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class AttachQuery : public DDLQuery
+{
+    public:
+        static PtrTo<AttachQuery> createDictionary(PtrTo<ClusterClause> clause, PtrTo<TableIdentifier> identifier);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // TableIdentifier
+        };
+
+        enum class QueryType
+        {
+            DICTIONARY,
+        };
+
+        const QueryType query_type;
+
+        AttachQuery(PtrTo<ClusterClause> clause, QueryType type, PtrList exprs);
+};
+
+}

src/Parsers/New/AST/CheckQuery.cpp

@@ -0,0 +1,44 @@
+#include <Parsers/New/AST/CheckQuery.h>
+
+#include <Interpreters/StorageID.h>
+#include <Parsers/ASTCheckQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/New/AST/AlterTableQuery.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+CheckQuery::CheckQuery(PtrTo<TableIdentifier> identifier, PtrTo<PartitionClause> clause) : Query{identifier, clause}
+{
+}
+
+ASTPtr CheckQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCheckQuery>();
+
+    auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+    query->database = table_id.database_name;
+    query->table = table_id.table_name;
+
+    if (has(PARTITION)) query->partition = get(PARTITION)->convertToOld();
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCheckStmt(ClickHouseParser::CheckStmtContext *ctx)
+{
+    auto partition = ctx->partitionClause() ? visit(ctx->partitionClause()).as<PtrTo<PartitionClause>>() : nullptr;
+    return std::make_shared<CheckQuery>(visit(ctx->tableIdentifier()), partition);
+}
+
+}

src/Parsers/New/AST/CheckQuery.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+
+namespace DB::AST
+{
+
+class CheckQuery : public Query
+{
+    public:
+        CheckQuery(PtrTo<TableIdentifier> identifier, PtrTo<PartitionClause> clause);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,       // TableIdentifier
+            PARTITION = 1,  // PartitionClause (optional)
+        };
+};
+
+}

src/Parsers/New/AST/ColumnExpr.cpp

@@ -0,0 +1,588 @@
+#include <Parsers/New/AST/ColumnExpr.h>
+
+#include <Parsers/ASTAsterisk.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/ASTQualifiedAsterisk.h>
+#include <Parsers/ASTSubquery.h>
+#include <Parsers/New/AST/ColumnTypeExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/ClickHouseLexer.h>
+#include <Parsers/New/ClickHouseParser.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::ErrorCodes
+{
+    extern int SYNTAX_ERROR;
+}
+
+namespace DB::AST
+{
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createAlias(PtrTo<ColumnExpr> expr, PtrTo<Identifier> alias)
+{
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::ALIAS, {expr, alias}));
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createAsterisk(PtrTo<TableIdentifier> identifier, bool single_column)
+{
+    auto expr = PtrTo<ColumnExpr>(new ColumnExpr(ExprType::ASTERISK, {identifier}));
+    expr->expect_single_column = single_column;
+    return expr;
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createFunction(PtrTo<Identifier> name, PtrTo<ColumnParamList> params, PtrTo<ColumnExprList> args)
+{
+    // FIXME: make sure that all function names are camel-case.
+
+    // Flatten some consequent binary operators to a single multi-operator, because they are left-associative.
+    if ((name->getName() == "or" || name->getName() == "and") && args && args->size() == 2)
+    {
+        const auto * left = (*args->begin())->as<ColumnExpr>();
+        const auto * right = (*++args->begin())->as<ColumnExpr>();
+
+        if (left && left->getType() == ExprType::FUNCTION && left->getFunctionName() == name->getName())
+        {
+            auto new_args = std::make_shared<ColumnExprList>();
+            for (const auto & arg : left->get(ARGS)->as<ColumnExprList &>())
+                new_args->push(std::static_pointer_cast<ColumnExpr>(arg));
+            new_args->push(std::static_pointer_cast<ColumnExpr>(*++args->begin()));
+            args = new_args;
+        }
+        else if (right && right->getType() == ExprType::FUNCTION && right->getFunctionName() == name->getName())
+        {
+            auto new_args = std::make_shared<ColumnExprList>();
+            new_args->push(std::static_pointer_cast<ColumnExpr>(*args->begin()));
+            for (const auto & arg : right->get(ARGS)->as<ColumnExprList &>())
+                new_args->push(std::static_pointer_cast<ColumnExpr>(arg));
+            args = new_args;
+        }
+    }
+
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::FUNCTION, {name, params, args}));
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createIdentifier(PtrTo<ColumnIdentifier> identifier)
+{
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::IDENTIFIER, {identifier}));
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createLambda(PtrTo<List<Identifier>> params, PtrTo<ColumnExpr> expr)
+{
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::LAMBDA, {params, expr}));
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createLiteral(PtrTo<Literal> literal)
+{
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::LITERAL, {literal}));
+}
+
+// static
+PtrTo<ColumnExpr> ColumnExpr::createSubquery(PtrTo<SelectUnionQuery> query, bool scalar)
+{
+    if (scalar) query->shouldBeScalar();
+    return PtrTo<ColumnExpr>(new ColumnExpr(ExprType::SUBQUERY, {query}));
+}
+
+ColumnExpr::ColumnExpr(ColumnExpr::ExprType type, PtrList exprs) : INode(exprs), expr_type(type)
+{
+}
+
+ASTPtr ColumnExpr::convertToOld() const
+{
+    switch (expr_type)
+    {
+        case ExprType::ALIAS:
+        {
+            ASTPtr expr = get(EXPR)->convertToOld();
+
+            if (auto * expr_with_alias = dynamic_cast<ASTWithAlias*>(expr.get()))
+                expr_with_alias->setAlias(get<Identifier>(ALIAS)->getName());
+            else
+                throw std::runtime_error("Trying to convert new expression with alias to old one without alias support: " + expr->getID());
+
+            return expr;
+        }
+        case ExprType::ASTERISK:
+            if (has(TABLE))
+            {
+                auto expr = std::make_shared<ASTQualifiedAsterisk>();
+                expr->children.push_back(get(TABLE)->convertToOld());
+                return expr;
+            }
+            return std::make_shared<ASTAsterisk>();
+        case ExprType::FUNCTION:
+        {
+            auto func = std::make_shared<ASTFunction>();
+
+            func->name = get<Identifier>(NAME)->getName();
+            if (has(ARGS))
+            {
+                func->arguments = get(ARGS)->convertToOld();
+                func->children.push_back(func->arguments);
+            }
+            if (has(PARAMS))
+            {
+                func->parameters = get(PARAMS)->convertToOld();
+                func->children.push_back(func->parameters);
+            }
+
+            return func;
+        }
+        case ExprType::IDENTIFIER:
+            return get(IDENTIFIER)->convertToOld();
+        case ExprType::LAMBDA:
+        {
+            auto func = std::make_shared<ASTFunction>();
+            auto tuple = std::make_shared<ASTFunction>();
+
+            func->name = "lambda";
+            func->arguments = std::make_shared<ASTExpressionList>();
+            func->arguments->children.push_back(tuple);
+            func->arguments->children.push_back(get(LAMBDA_EXPR)->convertToOld());
+            func->children.push_back(func->arguments);
+
+            tuple->name = "tuple";
+            tuple->arguments = get(LAMBDA_ARGS)->convertToOld();
+            tuple->children.push_back(tuple->arguments);
+
+            return func;
+        }
+        case ExprType::LITERAL:
+            return get(LITERAL)->convertToOld();
+        case ExprType::SUBQUERY:
+        {
+            auto subquery = std::make_shared<ASTSubquery>();
+            subquery->children.push_back(get(SUBQUERY)->convertToOld());
+            return subquery;
+        }
+    }
+    __builtin_unreachable();
+}
+
+String ColumnExpr::toString() const
+{
+    switch(expr_type)
+    {
+        case ExprType::LITERAL: return get(LITERAL)->toString();
+        default: return {};
+    }
+    __builtin_unreachable();
+}
+
+String ColumnExpr::dumpInfo() const
+{
+    switch(expr_type)
+    {
+        case ExprType::ALIAS: return "ALIAS";
+        case ExprType::ASTERISK: return "ASTERISK";
+        case ExprType::FUNCTION: return "FUNCTION";
+        case ExprType::IDENTIFIER: return "IDENTIFIER";
+        case ExprType::LAMBDA: return "LAMBDA";
+        case ExprType::LITERAL: return "LITERAL";
+        case ExprType::SUBQUERY: return "SUBQUERY";
+    }
+    __builtin_unreachable();
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitColumnArgExpr(ClickHouseParser::ColumnArgExprContext *ctx)
+{
+    if (ctx->columnExpr()) return visit(ctx->columnExpr());
+    if (ctx->columnLambdaExpr()) return visit(ctx->columnLambdaExpr());
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnArgList(ClickHouseParser::ColumnArgListContext *ctx)
+{
+    auto list = std::make_shared<ColumnExprList>();
+    for (auto * arg : ctx->columnArgExpr()) list->push(visit(arg));
+    return list;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprAlias(ClickHouseParser::ColumnExprAliasContext *ctx)
+{
+    if (ctx->AS()) return ColumnExpr::createAlias(visit(ctx->columnExpr()), visit(ctx->identifier()));
+    else return ColumnExpr::createAlias(visit(ctx->columnExpr()), visit(ctx->alias()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprAnd(ClickHouseParser::ColumnExprAndContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("and");
+    auto args = std::make_shared<ColumnExprList>();
+
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprArray(ClickHouseParser::ColumnExprArrayContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("array");
+    auto args = ctx->columnExprList() ? visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>() : nullptr;
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprArrayAccess(ClickHouseParser::ColumnExprArrayAccessContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("arrayElement");
+    auto args = std::make_shared<ColumnExprList>();
+
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprAsterisk(ClickHouseParser::ColumnExprAsteriskContext *ctx)
+{
+    auto table = ctx->tableIdentifier() ? visit(ctx->tableIdentifier()).as<PtrTo<TableIdentifier>>() : nullptr;
+    return ColumnExpr::createAsterisk(table, true);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprBetween(ClickHouseParser::ColumnExprBetweenContext *ctx)
+{
+    PtrTo<ColumnExpr> expr1, expr2;
+
+    {
+        auto name = std::make_shared<Identifier>(ctx->NOT() ? "lessOrEquals" : "greaterOrEquals");
+        auto args = std::make_shared<ColumnExprList>();
+        args->push(visit(ctx->columnExpr(0)));
+        args->push(visit(ctx->columnExpr(1)));
+        expr1 = ColumnExpr::createFunction(name, nullptr, args);
+    }
+
+    {
+        auto name = std::make_shared<Identifier>(ctx->NOT() ? "greaterOrEquals" : "lessOrEquals");
+        auto args = std::make_shared<ColumnExprList>();
+        args->push(visit(ctx->columnExpr(0)));
+        args->push(visit(ctx->columnExpr(2)));
+        expr2 = ColumnExpr::createFunction(name, nullptr, args);
+    }
+
+    auto name = std::make_shared<Identifier>("and");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(expr1);
+    args->push(expr2);
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprCase(ClickHouseParser::ColumnExprCaseContext *ctx)
+{
+    auto has_case_expr = (ctx->ELSE() && ctx->columnExpr().size() % 2 == 0) || (!ctx->ELSE() && ctx->columnExpr().size() % 2 == 1);
+    auto name = std::make_shared<Identifier>(has_case_expr ? "caseWithExpression" : "multiIf");
+    auto args = std::make_shared<ColumnExprList>();
+
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+    if (!ctx->ELSE()) args->push(ColumnExpr::createLiteral(Literal::createNull()));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprCast(ClickHouseParser::ColumnExprCastContext *ctx)
+{
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(visit(ctx->columnExpr()));
+    args->push(ColumnExpr::createLiteral(Literal::createString(visit(ctx->columnTypeExpr()).as<PtrTo<ColumnTypeExpr>>()->toString())));
+
+    return ColumnExpr::createFunction(std::make_shared<Identifier>("cast"), nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprDate(ClickHouseParser::ColumnExprDateContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("toDate");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(ColumnExpr::createLiteral(Literal::createString(ctx->STRING_LITERAL())));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprExtract(ClickHouseParser::ColumnExprExtractContext *ctx)
+{
+    String name;
+    auto args = std::make_shared<ColumnExprList>();
+
+    if (ctx->interval()->SECOND()) name = "toSecond";
+    else if (ctx->interval()->MINUTE()) name = "toMinute";
+    else if (ctx->interval()->HOUR()) name = "toHour";
+    else if (ctx->interval()->DAY()) name = "toDayOfMonth";
+    else if (ctx->interval()->WEEK())
+        throw Exception(
+            "The syntax 'EXTRACT(WEEK FROM date)' is not supported, cannot extract the number of a week", ErrorCodes::SYNTAX_ERROR);
+    else if (ctx->interval()->MONTH()) name = "toMonth";
+    else if (ctx->interval()->QUARTER()) name = "toQuarter";
+    else if (ctx->interval()->YEAR()) name = "toYear";
+    else __builtin_unreachable();
+
+    args->push(visit(ctx->columnExpr()));
+
+    return ColumnExpr::createFunction(std::make_shared<Identifier>(name), nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprFunction(ClickHouseParser::ColumnExprFunctionContext *ctx)
+{
+    auto name = visit(ctx->identifier()).as<PtrTo<Identifier>>();
+    auto params = ctx->columnExprList() ? visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>() : nullptr;
+    auto args = ctx->columnArgList() ? visit(ctx->columnArgList()).as<PtrTo<ColumnExprList>>() : nullptr;
+
+    if (ctx->DISTINCT()) name = std::make_shared<Identifier>(name->getName() + "Distinct");
+
+    return ColumnExpr::createFunction(name, params, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprIdentifier(ClickHouseParser::ColumnExprIdentifierContext *ctx)
+{
+    return ColumnExpr::createIdentifier(visit(ctx->columnIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprInterval(ClickHouseParser::ColumnExprIntervalContext *ctx)
+{
+    PtrTo<Identifier> name;
+    auto args = std::make_shared<ColumnExprList>();
+
+    if (ctx->interval()->SECOND()) name = std::make_shared<Identifier>("toIntervalSecond");
+    else if (ctx->interval()->MINUTE()) name = std::make_shared<Identifier>("toIntervalMinute");
+    else if (ctx->interval()->HOUR()) name = std::make_shared<Identifier>("toIntervalHour");
+    else if (ctx->interval()->DAY()) name = std::make_shared<Identifier>("toIntervalDay");
+    else if (ctx->interval()->WEEK()) name = std::make_shared<Identifier>("toIntervalWeek");
+    else if (ctx->interval()->MONTH()) name = std::make_shared<Identifier>("toIntervalMonth");
+    else if (ctx->interval()->QUARTER()) name = std::make_shared<Identifier>("toIntervalQuarter");
+    else if (ctx->interval()->YEAR()) name = std::make_shared<Identifier>("toIntervalYear");
+    else __builtin_unreachable();
+
+    args->push(visit(ctx->columnExpr()));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprIsNull(ClickHouseParser::ColumnExprIsNullContext *ctx)
+{
+    auto name = std::make_shared<Identifier>(ctx->NOT() ? "isNotNull" : "isNull");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(visit(ctx->columnExpr()));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprList(ClickHouseParser::ColumnExprListContext *ctx)
+{
+    auto list = std::make_shared<ColumnExprList>();
+    for (auto * expr : ctx->columnsExpr()) list->push(visit(expr));
+    return list;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprLiteral(ClickHouseParser::ColumnExprLiteralContext *ctx)
+{
+    return ColumnExpr::createLiteral(visit(ctx->literal()).as<PtrTo<Literal>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprNegate(ClickHouseParser::ColumnExprNegateContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("negate");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(visit(ctx->columnExpr()));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprNot(ClickHouseParser::ColumnExprNotContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("not");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(visit(ctx->columnExpr()));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprOr(ClickHouseParser::ColumnExprOrContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("or");
+
+    auto args = std::make_shared<ColumnExprList>();
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprParens(ClickHouseParser::ColumnExprParensContext *ctx)
+{
+    return visit(ctx->columnExpr());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprPrecedence1(ClickHouseParser::ColumnExprPrecedence1Context *ctx)
+{
+    PtrTo<Identifier> name;
+    if (ctx->ASTERISK()) name = std::make_shared<Identifier>("multiply");
+    else if (ctx->SLASH()) name = std::make_shared<Identifier>("divide");
+    else if (ctx->PERCENT()) name = std::make_shared<Identifier>("modulo");
+
+    auto args = std::make_shared<ColumnExprList>();
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprPrecedence2(ClickHouseParser::ColumnExprPrecedence2Context *ctx)
+{
+    PtrTo<Identifier> name;
+    if (ctx->PLUS()) name = std::make_shared<Identifier>("plus");
+    else if (ctx->DASH()) name = std::make_shared<Identifier>("minus");
+    else if (ctx->CONCAT()) name = std::make_shared<Identifier>("concat");
+
+    auto args = std::make_shared<ColumnExprList>();
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprPrecedence3(ClickHouseParser::ColumnExprPrecedence3Context *ctx)
+{
+    PtrTo<Identifier> name;
+    if (ctx->EQ_DOUBLE() || ctx->EQ_SINGLE()) name = std::make_shared<Identifier>("equals");
+    else if (ctx->NOT_EQ()) name = std::make_shared<Identifier>("notEquals");
+    else if (ctx->LE()) name = std::make_shared<Identifier>("lessOrEquals");
+    else if (ctx->GE()) name = std::make_shared<Identifier>("greaterOrEquals");
+    else if (ctx->LT()) name = std::make_shared<Identifier>("less");
+    else if (ctx->GT()) name = std::make_shared<Identifier>("greater");
+    else if (ctx->LIKE())
+    {
+        if (ctx->NOT()) name = std::make_shared<Identifier>("notLike");
+        else name = std::make_shared<Identifier>("like");
+    }
+    else if (ctx->ILIKE())
+    {
+        if (ctx->NOT()) name = std::make_shared<Identifier>("notILike");
+        else name = std::make_shared<Identifier>("ilike");
+    }
+    else if (ctx->IN())
+    {
+        if (ctx->GLOBAL())
+        {
+            if (ctx->NOT()) name = std::make_shared<Identifier>("globalNotIn");
+            else name = std::make_shared<Identifier>("globalIn");
+        }
+        else
+        {
+            if (ctx->NOT()) name = std::make_shared<Identifier>("notIn");
+            else name = std::make_shared<Identifier>("in");
+        }
+    }
+
+    auto args = std::make_shared<ColumnExprList>();
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprSubquery(ClickHouseParser::ColumnExprSubqueryContext *ctx)
+{
+    // IN-operator is special since it accepts non-scalar subqueries on the right side.
+    auto * parent = dynamic_cast<ClickHouseParser::ColumnExprPrecedence3Context*>(ctx->parent);
+    return ColumnExpr::createSubquery(visit(ctx->selectUnionStmt()), !(parent && parent->IN()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprSubstring(ClickHouseParser::ColumnExprSubstringContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("substring");
+    auto args = std::make_shared<ColumnExprList>();
+
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprTernaryOp(ClickHouseParser::ColumnExprTernaryOpContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("if");
+    auto args = std::make_shared<ColumnExprList>();
+
+    for (auto * expr : ctx->columnExpr()) args->push(visit(expr));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprTimestamp(ClickHouseParser::ColumnExprTimestampContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("toDateTime");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(ColumnExpr::createLiteral(Literal::createString(ctx->STRING_LITERAL())));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprTrim(ClickHouseParser::ColumnExprTrimContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("trim");
+    auto args = std::make_shared<ColumnExprList>();
+    auto params = std::make_shared<ColumnParamList>();
+
+    args->push(visit(ctx->columnExpr()));
+    // TODO: params->append(Literal::createString(???));
+    params->push(ColumnExpr::createLiteral(Literal::createString(ctx->STRING_LITERAL())));
+
+    return ColumnExpr::createFunction(name, params, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprTuple(ClickHouseParser::ColumnExprTupleContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("tuple");
+    auto args = visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>();
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnExprTupleAccess(ClickHouseParser::ColumnExprTupleAccessContext *ctx)
+{
+    auto name = std::make_shared<Identifier>("tupleElement");
+    auto args = std::make_shared<ColumnExprList>();
+
+    args->push(visit(ctx->columnExpr()));
+    args->push(ColumnExpr::createLiteral(Literal::createNumber(ctx->DECIMAL_LITERAL())));
+
+    return ColumnExpr::createFunction(name, nullptr, args);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnLambdaExpr(ClickHouseParser::ColumnLambdaExprContext *ctx)
+{
+    auto params = std::make_shared<List<Identifier>>();
+    for (auto * id : ctx->identifier()) params->push(visit(id));
+    return ColumnExpr::createLambda(params, visit(ctx->columnExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnsExprAsterisk(ClickHouseParser::ColumnsExprAsteriskContext *ctx)
+{
+    auto table = ctx->tableIdentifier() ? visit(ctx->tableIdentifier()).as<PtrTo<TableIdentifier>>() : nullptr;
+    return ColumnExpr::createAsterisk(table, false);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnsExprSubquery(ClickHouseParser::ColumnsExprSubqueryContext *ctx)
+{
+    return ColumnExpr::createSubquery(visit(ctx->selectUnionStmt()), false);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnsExprColumn(ClickHouseParser::ColumnsExprColumnContext *ctx)
+{
+    return visit(ctx->columnExpr());
+}
+
+}

src/Parsers/New/AST/ColumnExpr.h

@@ -0,0 +1,82 @@
+#pragma once
+
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+
+
+namespace DB::AST
+{
+
+class ColumnExpr : public INode
+{
+    public:
+        static PtrTo<ColumnExpr> createAlias(PtrTo<ColumnExpr> expr, PtrTo<Identifier> alias);
+        static PtrTo<ColumnExpr> createAsterisk(PtrTo<TableIdentifier> identifier, bool single_column);
+        static PtrTo<ColumnExpr> createFunction(PtrTo<Identifier> name, PtrTo<ColumnParamList> params, PtrTo<ColumnExprList> args);
+        static PtrTo<ColumnExpr> createIdentifier(PtrTo<ColumnIdentifier> identifier);
+        static PtrTo<ColumnExpr> createLambda(PtrTo<List<Identifier>> params, PtrTo<ColumnExpr> expr);
+        static PtrTo<ColumnExpr> createLiteral(PtrTo<Literal> literal);
+        static PtrTo<ColumnExpr> createSubquery(PtrTo<SelectUnionQuery> query, bool scalar);
+
+        enum class ExprType
+        {
+            ALIAS,
+            ASTERISK,
+            FUNCTION,
+            IDENTIFIER,
+            LAMBDA,
+            LITERAL,
+            SUBQUERY,
+        };
+
+        auto getType() const { return expr_type; };
+
+        // FUNCTION
+        auto getFunctionName() const { return get<Identifier>(NAME)->getName(); }
+        auto argumentsBegin() const { return has(ARGS) ? get<ColumnExprList>(ARGS)->begin() : end(); }
+        auto argumentsEnd() const { return has(ARGS) ? get<ColumnExprList>(ARGS)->end() : end(); }
+
+        // LITERAL
+        auto getLiteral() const { return std::static_pointer_cast<Literal>(get(LITERAL)); }
+
+        ASTPtr convertToOld() const override;
+        String toString() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            // ALIAS
+            EXPR = 0,   // ColumnExpr
+            ALIAS = 1,  // Identifier
+
+            // ASTERISK
+            TABLE = 0,  // TableIdentifier (optional)
+
+            // IDENTIFIER
+            IDENTIFIER = 0,  // ColumnIdentifier
+
+            // FUNCTION
+            NAME = 0,    // Identifier
+            PARAMS = 1,  // ColumnParamList (optional)
+            ARGS = 2,    // ColumnExprList (optional)
+
+            // LAMBDA
+            LAMBDA_ARGS = 0,
+            LAMBDA_EXPR = 1,
+
+            // LITERAL
+            LITERAL = 0,
+
+            // SUBQUERY
+            SUBQUERY = 0,
+        };
+
+        const ExprType expr_type;
+        bool expect_single_column = false;
+
+        ColumnExpr(ExprType type, PtrList exprs);
+
+        String dumpInfo() const override;
+};
+
+}

src/Parsers/New/AST/ColumnTypeExpr.cpp

@@ -0,0 +1,166 @@
+#include <Parsers/New/AST/ColumnTypeExpr.h>
+
+#include <Parsers/ASTFunction.h>
+#include <Parsers/ASTNameTypePair.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+EnumValue::EnumValue(PtrTo<StringLiteral> name, PtrTo<NumberLiteral> value) : INode{name, value}
+{
+}
+
+ASTPtr EnumValue::convertToOld() const
+{
+    auto func = std::make_shared<ASTFunction>();
+
+    func->name = "equals";
+    func->arguments = std::make_shared<ASTExpressionList>();
+    func->arguments->children.push_back(get(NAME)->convertToOld());
+    func->arguments->children.push_back(get(VALUE)->convertToOld());
+    func->children.push_back(func->arguments);
+
+    return func;
+}
+
+String EnumValue::toString() const
+{
+    return fmt::format("{} = {}", get(NAME)->toString(), get(VALUE)->toString());
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createSimple(PtrTo<Identifier> identifier)
+{
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::SIMPLE, {identifier}));
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createNamed(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExpr> type)
+{
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::NAMED, {identifier, type}));
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createComplex(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExprList> list)
+{
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::COMPLEX, {identifier, list}));
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createEnum(PtrTo<Identifier> identifier, PtrTo<EnumValueList> list)
+{
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::ENUM, {identifier, list}));
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createParam(PtrTo<Identifier> identifier, PtrTo<ColumnParamList> list)
+{
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::PARAM, {identifier, list}));
+}
+
+// static
+PtrTo<ColumnTypeExpr> ColumnTypeExpr::createNested(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExprList> list)
+{
+    // TODO: assert that |list| must contain only expressions of NAMED type
+    return PtrTo<ColumnTypeExpr>(new ColumnTypeExpr(ExprType::NESTED, {identifier, list}));
+}
+
+ColumnTypeExpr::ColumnTypeExpr(ExprType type, PtrList exprs) : INode(exprs), expr_type(type)
+{
+}
+
+ASTPtr ColumnTypeExpr::convertToOld() const
+{
+    if (expr_type == ExprType::NAMED)
+    {
+        auto pair = std::make_shared<ASTNameTypePair>();
+
+        pair->name = get<Identifier>(NAME)->getName();
+        pair->type = get(TYPE)->convertToOld();
+        pair->children.push_back(pair->type);
+
+        return pair;
+    }
+
+    auto func = std::make_shared<ASTFunction>();
+
+    func->name = get<Identifier>(NAME)->getName();
+    func->no_empty_args = true;
+    if (expr_type != ExprType::SIMPLE && has(LIST))
+    {
+        func->arguments = get(LIST)->convertToOld();
+        func->children.push_back(func->arguments);
+    }
+
+    return func;
+}
+
+String ColumnTypeExpr::toString() const
+{
+    switch(expr_type)
+    {
+        case ExprType::SIMPLE:
+            return get(NAME)->toString();
+        case ExprType::NAMED:
+            return get(NAME)->toString() + " " + get(TYPE)->toString();
+        case ExprType::COMPLEX:
+        case ExprType::ENUM:
+        case ExprType::PARAM:
+        case ExprType::NESTED:
+            return get(NAME)->toString() + "(" + (has(LIST) ? get(LIST)->toString() : "") + ")";
+    }
+    __builtin_unreachable();
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitColumnTypeExprSimple(ClickHouseParser::ColumnTypeExprSimpleContext *ctx)
+{
+    return ColumnTypeExpr::createSimple(visit(ctx->identifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnTypeExprParam(ClickHouseParser::ColumnTypeExprParamContext *ctx)
+{
+    auto list = ctx->columnExprList() ? visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>() : nullptr;
+    return ColumnTypeExpr::createParam(visit(ctx->identifier()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnTypeExprEnum(ClickHouseParser::ColumnTypeExprEnumContext *ctx)
+{
+    auto list = std::make_shared<EnumValueList>();
+    for (auto * value : ctx->enumValue()) list->push(visit(value));
+    return ColumnTypeExpr::createEnum(visit(ctx->identifier()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnTypeExprComplex(ClickHouseParser::ColumnTypeExprComplexContext *ctx)
+{
+    auto list = std::make_shared<ColumnTypeExprList>();
+    for (auto * expr : ctx->columnTypeExpr()) list->push(visit(expr));
+    return ColumnTypeExpr::createComplex(visit(ctx->identifier()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnTypeExprNested(ClickHouseParser::ColumnTypeExprNestedContext *ctx)
+{
+    auto list = std::make_shared<ColumnTypeExprList>();
+
+    for (size_t i = 0; i < ctx->columnTypeExpr().size(); ++i)
+        list->push(ColumnTypeExpr::createNamed(visit(ctx->identifier(i + 1)), visit(ctx->columnTypeExpr(i))));
+
+    return ColumnTypeExpr::createNested(visit(ctx->identifier(0)), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitEnumValue(ClickHouseParser::EnumValueContext *ctx)
+{
+    return std::make_shared<EnumValue>(Literal::createString(ctx->STRING_LITERAL()), visit(ctx->numberLiteral()));
+}
+
+}

src/Parsers/New/AST/ColumnTypeExpr.h

@@ -0,0 +1,62 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+#include <list>
+
+
+namespace DB::AST
+{
+
+class EnumValue : public INode
+{
+    public:
+        EnumValue(PtrTo<StringLiteral> name, PtrTo<NumberLiteral> value);
+
+        ASTPtr convertToOld() const override;
+        String toString() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,   // StringLiteral
+            VALUE = 1,  // NumberLiteral
+        };
+};
+
+class ColumnTypeExpr : public INode
+{
+    public:
+        static PtrTo<ColumnTypeExpr> createSimple(PtrTo<Identifier> identifier);
+        static PtrTo<ColumnTypeExpr> createNamed(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExpr> type);
+        static PtrTo<ColumnTypeExpr> createComplex(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExprList> list);
+        static PtrTo<ColumnTypeExpr> createEnum(PtrTo<Identifier> identifier, PtrTo<EnumValueList> list);
+        static PtrTo<ColumnTypeExpr> createParam(PtrTo<Identifier> identifier, PtrTo<ColumnParamList> list);
+        static PtrTo<ColumnTypeExpr> createNested(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExprList> list);
+
+        ASTPtr convertToOld() const override;
+        String toString() const override;
+
+    private:
+        enum class ExprType
+        {
+            SIMPLE,
+            NAMED,
+            COMPLEX,
+            ENUM,
+            PARAM,
+            NESTED,
+        };
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // Identifier
+            TYPE = 1,  // ColumnTypeExpr
+            LIST = 1,  // depends on |expr_type|
+        };
+
+        ExprType expr_type;
+
+        ColumnTypeExpr(ExprType type, PtrList exprs);
+};
+
+}

src/Parsers/New/AST/CreateDatabaseQuery.cpp

@@ -0,0 +1,51 @@
+#include <Parsers/New/AST/CreateDatabaseQuery.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/New/AST/EngineExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+CreateDatabaseQuery::CreateDatabaseQuery(
+    PtrTo<ClusterClause> cluster, bool if_not_exists_, PtrTo<DatabaseIdentifier> identifier, PtrTo<EngineExpr> expr)
+    : DDLQuery(cluster, {identifier, expr}), if_not_exists(if_not_exists_)
+{
+}
+
+ASTPtr CreateDatabaseQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    query->if_not_exists = if_not_exists;
+    query->database = get<DatabaseIdentifier>(NAME)->getName();
+    query->cluster = cluster_name;
+    if (has(ENGINE))
+    {
+        auto engine = std::make_shared<ASTStorage>();
+        engine->set(engine->engine, get(ENGINE)->convertToOld());
+        query->set(query->storage, engine);
+    }
+    // TODO: query->uuid
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCreateDatabaseStmt(ClickHouseParser::CreateDatabaseStmtContext *ctx)
+{
+    auto engine = ctx->engineExpr() ? visit(ctx->engineExpr()).as<PtrTo<EngineExpr>>() : nullptr;
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    return std::make_shared<CreateDatabaseQuery>(cluster, !!ctx->IF(), visit(ctx->databaseIdentifier()), engine);
+}
+
+}

src/Parsers/New/AST/CreateDatabaseQuery.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class CreateDatabaseQuery: public DDLQuery
+{
+    public:
+        CreateDatabaseQuery(PtrTo<ClusterClause> cluster, bool if_not_exists, PtrTo<DatabaseIdentifier> identifier, PtrTo<EngineExpr> expr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,    // DatabaseIdentifier
+            ENGINE = 1,  // EngineExpr (optional)
+        };
+
+        const bool if_not_exists;
+};
+
+}

src/Parsers/New/AST/CreateDictionaryQuery.cpp

@@ -0,0 +1,361 @@
+#include <Parsers/New/AST/CreateDictionaryQuery.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/AST/ColumnTypeExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/AST/SettingExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+#include <Poco/String.h>
+
+
+namespace DB::ErrorCodes
+{
+    extern const int SYNTAX_ERROR;
+}
+
+namespace DB::AST
+{
+
+// DictionaryAttributeExpr
+
+DictionaryAttributeExpr::DictionaryAttributeExpr(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExpr> type) : INode(MAX_INDEX)
+{
+    set(NAME, identifier);
+    set(TYPE, type);
+}
+
+void DictionaryAttributeExpr::setDefaultClause(PtrTo<Literal> literal)
+{
+    set(DEFAULT, literal);
+}
+
+void DictionaryAttributeExpr::setExpressionClause(PtrTo<ColumnExpr> expr)
+{
+    set(EXPRESSION, expr);
+}
+
+ASTPtr DictionaryAttributeExpr::convertToOld() const
+{
+    auto expr = std::make_shared<ASTDictionaryAttributeDeclaration>();
+
+    expr->name = get<Identifier>(NAME)->getName();
+    if (has(TYPE))
+    {
+        expr->type = get(TYPE)->convertToOld();
+        expr->children.push_back(expr->type);
+    }
+    if (has(DEFAULT))
+    {
+        expr->default_value = get(DEFAULT)->convertToOld();
+        expr->children.push_back(expr->default_value);
+    }
+    if (has(EXPRESSION))
+    {
+        expr->expression = get(EXPRESSION)->convertToOld();
+        expr->children.push_back(expr->expression);
+    }
+    expr->hierarchical = hierarchical;
+    expr->injective = injective;
+    expr->is_object_id = is_object_id;
+
+    return expr;
+}
+
+// DictionaryArgExpr
+
+DictionaryArgExpr::DictionaryArgExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExpr> expr) : INode{identifier, expr}
+{
+    if (expr->getType() != ColumnExpr::ExprType::LITERAL && expr->getType() != ColumnExpr::ExprType::IDENTIFIER
+        && expr->getType() != ColumnExpr::ExprType::FUNCTION)
+        throw DB::Exception(ErrorCodes::SYNTAX_ERROR, "Expected literal, identifier or function");
+}
+
+ASTPtr DictionaryArgExpr::convertToOld() const
+{
+    auto expr = std::make_shared<ASTPair>(false);  // FIXME: always true?
+
+    // TODO: probably there are more variants to parse.
+
+    expr->first = Poco::toLower(get<Identifier>(KEY)->getName());
+    expr->set(expr->second, get(VALUE)->convertToOld());
+
+    return expr;
+}
+
+// SourceClause
+
+SourceClause::SourceClause(PtrTo<Identifier> identifier, PtrTo<DictionaryArgList> list) : INode{identifier, list}
+{
+}
+
+ASTPtr SourceClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTFunctionWithKeyValueArguments>(true);  // FIXME: always true?
+
+    clause->name = Poco::toLower(get<Identifier>(NAME)->getName());
+    if (has(ARGS))
+    {
+        clause->elements = get(ARGS)->convertToOld();
+        clause->children.push_back(clause->elements);
+    }
+
+    return clause;
+}
+
+// LifetimeClause
+
+LifetimeClause::LifetimeClause(PtrTo<NumberLiteral> max, PtrTo<NumberLiteral> min) : INode{max, min}
+{
+}
+
+ASTPtr LifetimeClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTDictionaryLifetime>();
+
+    clause->max_sec = get(MAX)->convertToOld()->as<ASTLiteral>()->value.get<UInt64>();
+    if (has(MIN)) clause->min_sec = get(MIN)->convertToOld()->as<ASTLiteral>()->value.get<UInt64>();
+
+    return clause;
+}
+
+// LayoutClause
+
+LayoutClause::LayoutClause(PtrTo<Identifier> identifier, PtrTo<DictionaryArgList> list) : INode{identifier, list}
+{
+}
+
+ASTPtr LayoutClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTDictionaryLayout>();
+
+    clause->layout_type = Poco::toLower(get<Identifier>(NAME)->getName());
+    clause->has_brackets = true;  // FIXME: maybe not?
+    if (has(ARGS)) clause->set(clause->parameters, get(ARGS)->convertToOld());
+
+    return clause;
+}
+
+// RangeClause
+
+RangeClause::RangeClause(PtrTo<Identifier> max, PtrTo<Identifier> min) : INode{max, min}
+{
+}
+
+ASTPtr RangeClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTDictionaryRange>();
+
+    clause->max_attr_name = get<Identifier>(MAX)->getName();
+    clause->min_attr_name = get<Identifier>(MIN)->getName();
+
+    return clause;
+}
+
+// DictionarySettingsClause
+
+DictionarySettingsClause::DictionarySettingsClause(PtrTo<SettingExprList> list) : INode{list}
+{
+}
+
+ASTPtr DictionarySettingsClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTDictionarySettings>();
+
+    for (const auto & child : get(LIST)->as<SettingExprList &>())
+    {
+        const auto * setting = child->as<SettingExpr>();
+        clause->changes.emplace_back(setting->getName()->getName(), setting->getValue()->convertToOld()->as<ASTLiteral>()->value);
+    }
+
+    return clause;
+}
+
+// DictionaryEngineClause
+
+DictionaryEngineClause::DictionaryEngineClause(PtrTo<DictionaryPrimaryKeyClause> clause) : INode(MAX_INDEX)
+{
+    set(PRIMARY_KEY, clause);
+}
+
+void DictionaryEngineClause::setSourceClause(PtrTo<SourceClause> clause)
+{
+    set(SOURCE, clause);
+}
+
+void DictionaryEngineClause::setLifetimeClause(PtrTo<LifetimeClause> clause)
+{
+    set(LIFETIME, clause);
+}
+
+void DictionaryEngineClause::setLayoutClause(PtrTo<LayoutClause> clause)
+{
+    set(LAYOUT, clause);
+}
+
+void DictionaryEngineClause::setRangeClause(PtrTo<RangeClause> clause)
+{
+    set(RANGE, clause);
+}
+
+void DictionaryEngineClause::setSettingsClause(PtrTo<DictionarySettingsClause> clause)
+{
+    set(SETTINGS, clause);
+}
+
+ASTPtr DictionaryEngineClause::convertToOld() const
+{
+    auto clause = std::make_shared<ASTDictionary>();
+
+    if (has(PRIMARY_KEY)) clause->set(clause->primary_key, get(PRIMARY_KEY)->convertToOld());
+    if (has(SOURCE)) clause->set(clause->source, get(SOURCE)->convertToOld());
+    if (has(LIFETIME)) clause->set(clause->lifetime, get(LIFETIME)->convertToOld());
+    if (has(LAYOUT)) clause->set(clause->layout, get(LAYOUT)->convertToOld());
+    if (has(RANGE)) clause->set(clause->range, get(RANGE)->convertToOld());
+    if (has(SETTINGS)) clause->set(clause->dict_settings, get(SETTINGS)->convertToOld());
+
+    return clause;
+}
+
+// CreateDictionaryQuery
+
+CreateDictionaryQuery::CreateDictionaryQuery(
+    PtrTo<ClusterClause> cluster,
+    bool attach_,
+    bool if_not_exists_,
+    PtrTo<TableIdentifier> identifier,
+    PtrTo<UUIDClause> uuid,
+    PtrTo<DictionarySchemaClause> schema,
+    PtrTo<DictionaryEngineClause> engine)
+    : DDLQuery(cluster, {identifier, uuid, schema, engine}), attach(attach_), if_not_exists(if_not_exists_)
+{
+}
+
+ASTPtr CreateDictionaryQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid
+            = has(UUID) ? parseFromString<DB::UUID>(get(UUID)->convertToOld()->as<ASTLiteral>()->value.get<String>()) : table_id.uuid;
+    }
+
+    query->cluster = cluster_name;
+
+    query->is_dictionary = true;
+    query->attach = attach;
+    query->if_not_exists = if_not_exists;
+
+    query->set(query->dictionary_attributes_list, get(SCHEMA)->convertToOld());
+    query->set(query->dictionary, get(ENGINE)->convertToOld());
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCreateDictionaryStmt(ClickHouseParser::CreateDictionaryStmtContext *ctx)
+{
+    auto uuid = ctx->uuidClause() ? visit(ctx->uuidClause()).as<PtrTo<UUIDClause>>() : nullptr;
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto schema = ctx->dictionarySchemaClause() ? visit(ctx->dictionarySchemaClause()).as<PtrTo<DictionarySchemaClause>>() : nullptr;
+    auto engine = ctx->dictionaryEngineClause() ? visit(ctx->dictionaryEngineClause()).as<PtrTo<DictionaryEngineClause>>() : nullptr;
+    return std::make_shared<CreateDictionaryQuery>(
+        cluster, !!ctx->ATTACH(), !!ctx->IF(), visit(ctx->tableIdentifier()), uuid, schema, engine);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionaryArgExpr(ClickHouseParser::DictionaryArgExprContext *ctx)
+{
+    PtrTo<ColumnExpr> expr;
+    if (ctx->literal()) expr = ColumnExpr::createLiteral(visit(ctx->literal()));
+    else if (ctx->LPAREN()) expr = ColumnExpr::createFunction(visit(ctx->identifier(1)), nullptr, nullptr);
+    else expr = ColumnExpr::createIdentifier(visit(ctx->identifier(1)));
+    return std::make_shared<DictionaryArgExpr>(visit(ctx->identifier(0)), expr);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionaryAttrDfnt(ClickHouseParser::DictionaryAttrDfntContext *ctx)
+{
+    auto expr = std::make_shared<DictionaryAttributeExpr>(visit(ctx->identifier()), visit(ctx->columnTypeExpr()));
+    if (!ctx->DEFAULT().empty()) expr->setDefaultClause(visit(ctx->literal(0)));
+    if (!ctx->EXPRESSION().empty()) expr->setExpressionClause(visit(ctx->columnExpr(0)));
+    if (!ctx->HIERARCHICAL().empty()) expr->setHierarchicalFlag();
+    if (!ctx->INJECTIVE().empty()) expr->setInjectiveFlag();
+    if (!ctx->IS_OBJECT_ID().empty()) expr->setIsObjectIdFlag();
+    return expr;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionaryEngineClause(ClickHouseParser::DictionaryEngineClauseContext *ctx)
+{
+    auto primary_key
+        = ctx->dictionaryPrimaryKeyClause() ? visit(ctx->dictionaryPrimaryKeyClause()).as<PtrTo<DictionaryPrimaryKeyClause>>() : nullptr;
+    auto clause = std::make_shared<DictionaryEngineClause>(primary_key);
+    if (!ctx->sourceClause().empty()) clause->setSourceClause(visit(ctx->sourceClause(0)));
+    if (!ctx->lifetimeClause().empty()) clause->setLifetimeClause(visit(ctx->lifetimeClause(0)));
+    if (!ctx->layoutClause().empty()) clause->setLayoutClause(visit(ctx->layoutClause(0)));
+    if (!ctx->rangeClause().empty()) clause->setRangeClause(visit(ctx->rangeClause(0)));
+    if (!ctx->dictionarySettingsClause().empty()) clause->setSettingsClause(visit(ctx->dictionarySettingsClause(0)));
+    return clause;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionaryPrimaryKeyClause(ClickHouseParser::DictionaryPrimaryKeyClauseContext *ctx)
+{
+    return std::make_shared<DictionaryPrimaryKeyClause>(visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionarySchemaClause(ClickHouseParser::DictionarySchemaClauseContext *ctx)
+{
+    auto list = std::make_shared<DictionaryAttributeList>();
+    for (auto * attr : ctx->dictionaryAttrDfnt()) list->push(visit(attr));
+    return std::make_shared<DictionarySchemaClause>(list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDictionarySettingsClause(ClickHouseParser::DictionarySettingsClauseContext *ctx)
+{
+    return std::make_shared<DictionarySettingsClause>(visit(ctx->settingExprList()).as<PtrTo<SettingExprList>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitLayoutClause(ClickHouseParser::LayoutClauseContext *ctx)
+{
+    auto list = ctx->dictionaryArgExpr().empty() ? nullptr : std::make_shared<DictionaryArgList>();
+    for (auto * arg : ctx->dictionaryArgExpr()) list->push(visit(arg));
+    return std::make_shared<LayoutClause>(visit(ctx->identifier()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitLifetimeClause(ClickHouseParser::LifetimeClauseContext *ctx)
+{
+    if (ctx->DECIMAL_LITERAL().size() == 1) return std::make_shared<LifetimeClause>(Literal::createNumber(ctx->DECIMAL_LITERAL(0)));
+    if (ctx->MAX()->getSymbol()->getTokenIndex() < ctx->MIN()->getSymbol()->getTokenIndex())
+        return std::make_shared<LifetimeClause>(
+            Literal::createNumber(ctx->DECIMAL_LITERAL(0)), Literal::createNumber(ctx->DECIMAL_LITERAL(1)));
+    else
+        return std::make_shared<LifetimeClause>(
+            Literal::createNumber(ctx->DECIMAL_LITERAL(1)), Literal::createNumber(ctx->DECIMAL_LITERAL(0)));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitRangeClause(ClickHouseParser::RangeClauseContext *ctx)
+{
+    if (ctx->MAX()->getSymbol()->getTokenIndex() < ctx->MIN()->getSymbol()->getTokenIndex())
+        return std::make_shared<RangeClause>(visit(ctx->identifier(0)), visit(ctx->identifier(1)));
+    else
+        return std::make_shared<RangeClause>(visit(ctx->identifier(1)), visit(ctx->identifier(0)));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSourceClause(ClickHouseParser::SourceClauseContext *ctx)
+{
+    auto list = ctx->dictionaryArgExpr().empty() ? nullptr : std::make_shared<DictionaryArgList>();
+    for (auto * arg : ctx->dictionaryArgExpr()) list->push(visit(arg));
+    return std::make_shared<SourceClause>(visit(ctx->identifier()), list);
+}
+
+}

src/Parsers/New/AST/CreateDictionaryQuery.h

@@ -0,0 +1,183 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class DictionaryAttributeExpr : public INode
+{
+    public:
+        DictionaryAttributeExpr(PtrTo<Identifier> identifier, PtrTo<ColumnTypeExpr> type);
+
+        void setDefaultClause(PtrTo<Literal> literal);
+        void setExpressionClause(PtrTo<ColumnExpr> expr);
+
+        void setHierarchicalFlag() { hierarchical = true; }
+        void setInjectiveFlag() { injective = true; }
+        void setIsObjectIdFlag() { is_object_id = true; }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,    // Identifier
+            TYPE,        // ColumnTypeExpr
+            DEFAULT,     // Literal (optional)
+            EXPRESSION,  // ColumnExpr (optional)
+
+            MAX_INDEX,
+        };
+
+        bool hierarchical = false, injective = false, is_object_id = false;
+};
+
+using DictionaryPrimaryKeyClause = SimpleClause<ColumnExprList>;
+
+using DictionarySchemaClause = SimpleClause<DictionaryAttributeList>;
+
+class DictionaryArgExpr : public INode
+{
+    public:
+        explicit DictionaryArgExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExpr> expr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            KEY = 0,  // Identifier
+            VALUE,    // ColumnExpr: literal, identifier or function
+        };
+};
+
+class SourceClause : public INode
+{
+    public:
+        SourceClause(PtrTo<Identifier> identifier, PtrTo<DictionaryArgList> list);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // Identifier
+            ARGS = 1,  // DictionaryArgList (optional)
+        };
+};
+
+class LifetimeClause : public INode
+{
+    public:
+        explicit LifetimeClause(PtrTo<NumberLiteral> max, PtrTo<NumberLiteral> min = nullptr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            MAX = 0,  // NumberLiteral
+            MIN,      // NumberLiteral (optional)
+        };
+};
+
+class LayoutClause : public INode
+{
+    public:
+        LayoutClause(PtrTo<Identifier> identifier, PtrTo<DictionaryArgList> list);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // Identifier
+            ARGS = 1,  // DictionaryArgList (optional)
+        };
+};
+
+class RangeClause : public INode
+{
+    public:
+        RangeClause(PtrTo<Identifier> max, PtrTo<Identifier> min);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            MAX = 0,  // Identifier
+            MIN,      // Identifier
+        };
+};
+
+class DictionarySettingsClause : public INode
+{
+    public:
+        explicit DictionarySettingsClause(PtrTo<SettingExprList> list);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            LIST = 0,  // SettingExprList
+        };
+};
+
+class DictionaryEngineClause : public INode
+{
+    public:
+        explicit DictionaryEngineClause(PtrTo<DictionaryPrimaryKeyClause> clause);
+
+        void setSourceClause(PtrTo<SourceClause> clause);
+        void setLifetimeClause(PtrTo<LifetimeClause> clause);
+        void setLayoutClause(PtrTo<LayoutClause> clause);
+        void setRangeClause(PtrTo<RangeClause> clause);
+        void setSettingsClause(PtrTo<DictionarySettingsClause> clause);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            PRIMARY_KEY = 0,  // DictionaryPrimaryKeyClause
+            SOURCE,           // SourceClause (optional)
+            LIFETIME,         // LifetimeClause (optional)
+            LAYOUT,           // LayoutClause (optional)
+            RANGE,            // RangeClause (optional)
+            SETTINGS,         // DictionarySettingsClause (optional)
+
+            MAX_INDEX,
+        };
+};
+
+class CreateDictionaryQuery : public DDLQuery
+{
+    public:
+        CreateDictionaryQuery(
+            PtrTo<ClusterClause> cluster,
+            bool attach,
+            bool if_not_exists,
+            PtrTo<TableIdentifier> identifier,
+            PtrTo<UUIDClause> uuid,
+            PtrTo<DictionarySchemaClause> schema,
+            PtrTo<DictionaryEngineClause> engine);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // TableIdentifier
+            UUID,      // UUIDClause (optional)
+            SCHEMA,    // DictionarySchemaClause
+            ENGINE,    // DictionaryEngineClause
+        };
+
+        const bool attach, if_not_exists;
+};
+
+}

src/Parsers/New/AST/CreateLiveViewQuery.cpp

@@ -0,0 +1,87 @@
+#include <Parsers/New/AST/CreateLiveViewQuery.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/New/AST/CreateTableQuery.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+CreateLiveViewQuery::CreateLiveViewQuery(
+    PtrTo<ClusterClause> cluster,
+    bool attach_,
+    bool if_not_exists_,
+    PtrTo<TableIdentifier> identifier,
+    PtrTo<UUIDClause> uuid,
+    PtrTo<NumberLiteral> timeout,
+    PtrTo<DestinationClause> destination,
+    PtrTo<TableSchemaClause> schema,
+    PtrTo<SelectUnionQuery> query)
+    : DDLQuery(cluster, {identifier, uuid, timeout, destination, schema, query}), attach(attach_), if_not_exists(if_not_exists_)
+{
+}
+
+ASTPtr CreateLiveViewQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid
+            = has(UUID) ? parseFromString<DB::UUID>(get(UUID)->convertToOld()->as<ASTLiteral>()->value.get<String>()) : table_id.uuid;
+    }
+
+    if (has(TIMEOUT))
+        query->live_view_timeout.emplace(get(TIMEOUT)->convertToOld()->as<ASTLiteral>()->value.get<UInt64>());
+
+    if (has(DESTINATION))
+        query->to_table_id = getTableIdentifier(get(DESTINATION)->convertToOld());
+
+    if (has(SCHEMA))
+    {
+        assert(get<TableSchemaClause>(SCHEMA)->getType() == TableSchemaClause::ClauseType::DESCRIPTION);
+        query->set(query->columns_list, get(SCHEMA)->convertToOld());
+    }
+
+    query->attach = attach;
+    query->if_not_exists = if_not_exists;
+    query->is_live_view = true;
+    query->set(query->select, get(SUBQUERY)->convertToOld());
+    query->cluster = cluster_name;
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCreateLiveViewStmt(ClickHouseParser::CreateLiveViewStmtContext *ctx)
+{
+    auto uuid = ctx->uuidClause() ? visit(ctx->uuidClause()).as<PtrTo<UUIDClause>>() : nullptr;
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto timeout = ctx->DECIMAL_LITERAL() ? Literal::createNumber(ctx->DECIMAL_LITERAL()) : nullptr;
+    auto destination = ctx->destinationClause() ? visit(ctx->destinationClause()).as<PtrTo<DestinationClause>>() : nullptr;
+    auto schema = ctx->tableSchemaClause() ? visit(ctx->tableSchemaClause()).as<PtrTo<TableSchemaClause>>() : nullptr;
+    if (ctx->TIMEOUT() && !timeout) timeout = Literal::createNumber(std::to_string(DEFAULT_TEMPORARY_LIVE_VIEW_TIMEOUT_SEC));
+    return std::make_shared<CreateLiveViewQuery>(
+        cluster,
+        !!ctx->ATTACH(),
+        !!ctx->IF(),
+        visit(ctx->tableIdentifier()),
+        uuid,
+        timeout,
+        destination,
+        schema,
+        visit(ctx->subqueryClause()));
+}
+
+}

src/Parsers/New/AST/CreateLiveViewQuery.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class CreateLiveViewQuery : public DDLQuery
+{
+    public:
+        CreateLiveViewQuery(
+            PtrTo<ClusterClause> cluster,
+            bool attach,
+            bool if_not_exists,
+            PtrTo<TableIdentifier> identifier,
+            PtrTo<UUIDClause> uuid,
+            PtrTo<NumberLiteral> timeout,
+            PtrTo<DestinationClause> destination,
+            PtrTo<TableSchemaClause> schema,
+            PtrTo<SelectUnionQuery> query);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,     // TableIdentifier
+            UUID,         // UUIDClause (optional)
+            TIMEOUT,      // NumberLiteral (optional)
+            DESTINATION,  // DestinationClause (optional)
+            SCHEMA,       // TableSchemaClause (optional)
+            SUBQUERY,     // SelectUnionQuery
+        };
+
+        const bool attach, if_not_exists;
+};
+
+}

src/Parsers/New/AST/CreateMaterializedViewQuery.cpp

@@ -0,0 +1,100 @@
+#include <Parsers/New/AST/CreateMaterializedViewQuery.h>
+
+#include <IO/ReadHelpers.h>
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/New/AST/CreateTableQuery.h>
+#include <Parsers/New/AST/EngineExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+CreateMaterializedViewQuery::CreateMaterializedViewQuery(
+    PtrTo<ClusterClause> cluster,
+    bool attach_,
+    bool if_not_exists_,
+    bool populate_,
+    PtrTo<TableIdentifier> identifier,
+    PtrTo<UUIDClause> uuid,
+    PtrTo<TableSchemaClause> schema,
+    PtrTo<DestinationClause> destination,
+    PtrTo<EngineClause> engine,
+    PtrTo<SelectUnionQuery> query)
+    : DDLQuery(cluster, {identifier, uuid, schema, destination, engine, query})
+    , attach(attach_)
+    , if_not_exists(if_not_exists_)
+    , populate(populate_)
+{
+    assert(!destination != !engine);
+}
+
+ASTPtr CreateMaterializedViewQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid
+            = has(UUID) ? parseFromString<DB::UUID>(get(UUID)->convertToOld()->as<ASTLiteral>()->value.get<String>()) : table_id.uuid;
+    }
+
+    if (has(DESTINATION))
+        query->to_table_id = getTableIdentifier(get(DESTINATION)->convertToOld());
+    else if (has(ENGINE))
+    {
+        query->set(query->storage, get(ENGINE)->convertToOld());
+        query->is_populate = populate;
+    }
+
+    if (has(SCHEMA))
+    {
+        assert(get<TableSchemaClause>(SCHEMA)->getType() == TableSchemaClause::ClauseType::DESCRIPTION);
+        query->set(query->columns_list, get(SCHEMA)->convertToOld());
+    }
+
+    query->attach = attach;
+    query->if_not_exists = if_not_exists;
+    query->is_materialized_view = true;
+    query->set(query->select, get(SUBQUERY)->convertToOld());
+    query->cluster = cluster_name;
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCreateMaterializedViewStmt(ClickHouseParser::CreateMaterializedViewStmtContext *ctx)
+{
+    auto uuid = ctx->uuidClause() ? visit(ctx->uuidClause()).as<PtrTo<UUIDClause>>() : nullptr;
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto schema = ctx->tableSchemaClause() ? visit(ctx->tableSchemaClause()).as<PtrTo<TableSchemaClause>>() : nullptr;
+    auto engine = ctx->engineClause() ? visit(ctx->engineClause()).as<PtrTo<EngineClause>>() : nullptr;
+    auto destination = ctx->destinationClause() ? visit(ctx->destinationClause()).as<PtrTo<DestinationClause>>() : nullptr;
+    return std::make_shared<CreateMaterializedViewQuery>(
+        cluster,
+        !!ctx->ATTACH(),
+        !!ctx->IF(),
+        !!ctx->POPULATE(),
+        visit(ctx->tableIdentifier()),
+        uuid,
+        schema,
+        destination,
+        engine,
+        visit(ctx->subqueryClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDestinationClause(ClickHouseParser::DestinationClauseContext *ctx)
+{
+    return std::make_shared<DestinationClause>(visit(ctx->tableIdentifier()).as<PtrTo<TableIdentifier>>());
+}
+
+}

src/Parsers/New/AST/CreateMaterializedViewQuery.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class CreateMaterializedViewQuery : public DDLQuery
+{
+    public:
+        CreateMaterializedViewQuery(
+            PtrTo<ClusterClause> cluster,
+            bool attach,
+            bool if_not_exists,
+            bool populate,
+            PtrTo<TableIdentifier> identifier,
+            PtrTo<UUIDClause> uuid,
+            PtrTo<TableSchemaClause> schema,
+            PtrTo<DestinationClause> destination,
+            PtrTo<EngineClause> engine,
+            PtrTo<SelectUnionQuery> query);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,     // TableIdentifier
+            UUID,         // UUIDClause (optional)
+            SCHEMA,       // TableSchemaClause (optional)
+            DESTINATION,  // DestinationClause (optional)
+            ENGINE,       // EngineClause (optional)
+            SUBQUERY,     // SelectUnionQuery
+        };
+
+        const bool attach, if_not_exists, populate;
+};
+
+}

src/Parsers/New/AST/CreateTableQuery.cpp

@@ -0,0 +1,219 @@
+#include <Parsers/New/AST/CreateTableQuery.h>
+
+#include <IO/ReadHelpers.h>
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/New/AST/EngineExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/AST/TableElementExpr.h>
+#include <Parsers/New/AST/TableExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<TableSchemaClause> TableSchemaClause::createDescription(PtrTo<TableElementList> list)
+{
+    return PtrTo<TableSchemaClause>(new TableSchemaClause(ClauseType::DESCRIPTION, {list}));
+}
+
+// static
+PtrTo<TableSchemaClause> TableSchemaClause::createAsTable(PtrTo<TableIdentifier> identifier)
+{
+    return PtrTo<TableSchemaClause>(new TableSchemaClause(ClauseType::TABLE, {identifier}));
+}
+
+// static
+PtrTo<TableSchemaClause> TableSchemaClause::createAsFunction(PtrTo<TableFunctionExpr> expr)
+{
+    return PtrTo<TableSchemaClause>(new TableSchemaClause(ClauseType::FUNCTION, {expr}));
+}
+
+TableSchemaClause::TableSchemaClause(ClauseType type, PtrList exprs) : INode(exprs), clause_type(type)
+{
+}
+
+ASTPtr TableSchemaClause::convertToOld() const
+{
+    switch(clause_type)
+    {
+        case ClauseType::DESCRIPTION:
+        {
+            auto columns = std::make_shared<ASTColumns>();
+
+            auto column_list = std::make_shared<ASTExpressionList>();
+            auto constraint_list = std::make_shared<ASTExpressionList>();
+            auto index_list = std::make_shared<ASTExpressionList>();
+
+            for (const auto & element : get(ELEMENTS)->as<TableElementList &>())
+            {
+                switch(element->as<TableElementExpr>()->getType())
+                {
+                    case TableElementExpr::ExprType::COLUMN:
+                        column_list->children.push_back(element->convertToOld());
+                        break;
+                    case TableElementExpr::ExprType::CONSTRAINT:
+                        constraint_list->children.push_back(element->convertToOld());
+                        break;
+                    case TableElementExpr::ExprType::INDEX:
+                        index_list->children.push_back(element->convertToOld());
+                        break;
+                }
+            }
+
+            if (!column_list->children.empty()) columns->set(columns->columns, column_list);
+            if (!constraint_list->children.empty()) columns->set(columns->constraints, constraint_list);
+            if (!index_list->children.empty()) columns->set(columns->indices, index_list);
+
+            return columns;
+        }
+        case ClauseType::FUNCTION:
+        case ClauseType::TABLE:
+            return get(EXPR)->convertToOld();
+    }
+    __builtin_unreachable();  // FIXME: old gcc compilers complain about reaching end of non-void function
+}
+
+String TableSchemaClause::dumpInfo() const
+{
+    switch(clause_type)
+    {
+        case ClauseType::DESCRIPTION: return "Description";
+        case ClauseType::FUNCTION: return "Function";
+        case ClauseType::TABLE: return "Table";
+    }
+    __builtin_unreachable();  // FIXME: old gcc compilers complain about reaching end of non-void function
+}
+
+CreateTableQuery::CreateTableQuery(
+    PtrTo<ClusterClause> cluster,
+    bool attach_,
+    bool temporary_,
+    bool if_not_exists_,
+    PtrTo<TableIdentifier> identifier,
+    PtrTo<UUIDClause> uuid,
+    PtrTo<TableSchemaClause> schema,
+    PtrTo<EngineClause> engine,
+    PtrTo<SelectUnionQuery> query)
+    : DDLQuery(cluster, {identifier, uuid, schema, engine, query}), attach(attach_), temporary(temporary_), if_not_exists(if_not_exists_)
+{
+}
+
+ASTPtr CreateTableQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid
+            = has(UUID) ? parseFromString<DB::UUID>(get(UUID)->convertToOld()->as<ASTLiteral>()->value.get<String>()) : table_id.uuid;
+    }
+
+    query->cluster = cluster_name;
+
+    query->attach = attach;
+    query->if_not_exists = if_not_exists;
+    query->temporary = temporary;
+
+    if (has(SCHEMA))
+    {
+        switch(get<TableSchemaClause>(SCHEMA)->getType())
+        {
+            case TableSchemaClause::ClauseType::DESCRIPTION:
+            {
+                query->set(query->columns_list, get(SCHEMA)->convertToOld());
+                break;
+            }
+            case TableSchemaClause::ClauseType::TABLE:
+            {
+                auto table_id = getTableIdentifier(get(SCHEMA)->convertToOld());
+                query->as_database = table_id.database_name;
+                query->as_table = table_id.table_name;
+                break;
+            }
+            case TableSchemaClause::ClauseType::FUNCTION:
+            {
+                query->as_table_function = get(SCHEMA)->convertToOld();
+                break;
+            }
+        }
+    }
+    if (has(ENGINE)) query->set(query->storage, get(ENGINE)->convertToOld());
+    if (has(SUBQUERY)) query->set(query->select, get(SUBQUERY)->convertToOld());
+
+    return query;
+}
+
+String CreateTableQuery::dumpInfo() const
+{
+    String info;
+    if (attach) info += "attach=true, ";
+    else info += "attach=false, ";
+    if (temporary) info += "temporary=true, ";
+    else info += "temporary=false, ";
+    if (if_not_exists) info += "if_not_exists=true";
+    else info += "if_not_exists=false";
+    return info;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+// TODO: assert(!(ctx->parent->TEMPORARY() ^ ctx->engineClause()))
+
+antlrcpp::Any ParseTreeVisitor::visitClusterClause(ClickHouseParser::ClusterClauseContext *ctx)
+{
+    auto literal = ctx->STRING_LITERAL() ? Literal::createString(ctx->STRING_LITERAL())
+                                         : Literal::createString(ctx->identifier()->getText());
+    return std::make_shared<ClusterClause>(literal);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitCreateTableStmt(ClickHouseParser::CreateTableStmtContext *ctx)
+{
+    auto uuid = ctx->uuidClause() ? visit(ctx->uuidClause()).as<PtrTo<UUIDClause>>() : nullptr;
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto schema = ctx->tableSchemaClause() ? visit(ctx->tableSchemaClause()).as<PtrTo<TableSchemaClause>>() : nullptr;
+    auto engine = ctx->engineClause() ? visit(ctx->engineClause()).as<PtrTo<EngineClause>>() : nullptr;
+    auto query = ctx->subqueryClause() ? visit(ctx->subqueryClause()).as<PtrTo<SelectUnionQuery>>() : nullptr;
+    return std::make_shared<CreateTableQuery>(
+        cluster, !!ctx->ATTACH(), !!ctx->TEMPORARY(), !!ctx->IF(), visit(ctx->tableIdentifier()), uuid, schema, engine, query);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSchemaDescriptionClause(ClickHouseParser::SchemaDescriptionClauseContext *ctx)
+{
+    auto elems = std::make_shared<TableElementList>();
+    for (auto * elem : ctx->tableElementExpr()) elems->push(visit(elem));
+    return TableSchemaClause::createDescription(elems);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSchemaAsTableClause(ClickHouseParser::SchemaAsTableClauseContext *ctx)
+{
+    return TableSchemaClause::createAsTable(visit(ctx->tableIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSchemaAsFunctionClause(ClickHouseParser::SchemaAsFunctionClauseContext *ctx)
+{
+    return TableSchemaClause::createAsFunction(visit(ctx->tableFunctionExpr()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSubqueryClause(ClickHouseParser::SubqueryClauseContext *ctx)
+{
+    return visit(ctx->selectUnionStmt());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitUuidClause(ClickHouseParser::UuidClauseContext *ctx)
+{
+    return std::make_shared<UUIDClause>(Literal::createString(ctx->STRING_LITERAL()));
+}
+
+}

src/Parsers/New/AST/CreateTableQuery.h

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+#include "Parsers/New/AST/SelectUnionQuery.h"
+
+
+namespace DB::AST
+{
+
+class TableSchemaClause : public INode
+{
+    public:
+        static PtrTo<TableSchemaClause> createDescription(PtrTo<TableElementList> list);
+        static PtrTo<TableSchemaClause> createAsTable(PtrTo<TableIdentifier> identifier);
+        static PtrTo<TableSchemaClause> createAsFunction(PtrTo<TableFunctionExpr> expr);
+
+        enum class ClauseType
+        {
+            DESCRIPTION,
+            TABLE,
+            FUNCTION,
+        };
+
+        auto getType() const { return clause_type; }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            // DESCRIPTION
+            ELEMENTS = 0,  // TableElementList
+
+            // TABLE and FUNCTION
+            EXPR = 0,      // TableIdentifier or TableFunctionExpr
+        };
+
+        ClauseType clause_type;
+
+        TableSchemaClause(ClauseType type, PtrList exprs);
+
+        String dumpInfo() const override;
+};
+
+class CreateTableQuery : public DDLQuery
+{
+    public:
+        CreateTableQuery(
+            PtrTo<ClusterClause> cluster,
+            bool attach,
+            bool temporary,
+            bool if_not_exists,
+            PtrTo<TableIdentifier> identifier,
+            PtrTo<UUIDClause> uuid,
+            PtrTo<TableSchemaClause> schema,
+            PtrTo<EngineClause> engine,
+            PtrTo<SelectUnionQuery> query);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // TableIdentifier
+            UUID,      // UUIDClause (optional)
+            SCHEMA,    // TableSchemaClause
+            ENGINE,    // EngineClause
+            SUBQUERY,  // SelectUnionQuery
+        };
+
+        const bool attach, temporary, if_not_exists;
+
+        String dumpInfo() const override;
+};
+
+}

src/Parsers/New/AST/CreateViewQuery.cpp

@@ -0,0 +1,62 @@
+#include <Parsers/New/AST/CreateViewQuery.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/New/AST/CreateTableQuery.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+CreateViewQuery::CreateViewQuery(
+    PtrTo<ClusterClause> cluster,
+    bool attach_,
+    bool replace_,
+    bool if_not_exists_,
+    PtrTo<TableIdentifier> identifier,
+    PtrTo<TableSchemaClause> clause,
+    PtrTo<SelectUnionQuery> query)
+    : DDLQuery(cluster, {identifier, clause, query}), attach(attach_), replace(replace_), if_not_exists(if_not_exists_)
+{
+}
+
+ASTPtr CreateViewQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTCreateQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(NAME)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid = table_id.uuid;
+    }
+
+    query->attach = attach;
+    query->replace_view = replace;
+    query->if_not_exists = if_not_exists;
+    query->is_view = true;
+    query->cluster = cluster_name;
+
+    if (has(SCHEMA)) query->set(query->columns_list, get(SCHEMA)->convertToOld());
+    query->set(query->select, get(SUBQUERY)->convertToOld());
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitCreateViewStmt(ClickHouseParser::CreateViewStmtContext *ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto schema = ctx->tableSchemaClause() ? visit(ctx->tableSchemaClause()).as<PtrTo<TableSchemaClause>>() : nullptr;
+    return std::make_shared<CreateViewQuery>(
+        cluster, !!ctx->ATTACH(), !!ctx->REPLACE(), !!ctx->IF(), visit(ctx->tableIdentifier()), schema, visit(ctx->subqueryClause()));
+}
+
+}

src/Parsers/New/AST/CreateViewQuery.h

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class CreateViewQuery : public DDLQuery
+{
+    public:
+        CreateViewQuery(
+            PtrTo<ClusterClause> cluster,
+            bool attach,
+            bool replace,
+            bool if_not_exists,
+            PtrTo<TableIdentifier> identifier,
+            PtrTo<TableSchemaClause> clause,
+            PtrTo<SelectUnionQuery> query);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,      // TableIdentifier
+            SCHEMA = 1,    // TableSchemaClause (optional)
+            SUBQUERY = 2,  // SelectUnionQuery
+        };
+
+        const bool attach, replace, if_not_exists;
+};
+
+}

src/Parsers/New/AST/DDLQuery.cpp

@@ -0,0 +1,6 @@
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+}

src/Parsers/New/AST/DDLQuery.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+#include <Parsers/ASTLiteral.h>
+#include <Parsers/ASTQueryWithOnCluster.h>
+#include <Parsers/New/AST/Identifier.h>
+
+
+namespace DB::AST
+{
+
+class DDLQuery : public Query
+{
+    protected:
+        DDLQuery(PtrTo<ClusterClause> cluster, std::initializer_list<Ptr> list)
+            : Query(list), cluster_name(cluster ? cluster->convertToOld()->as<ASTLiteral>()->value.get<String>() : String{})
+        {
+        }
+
+        DDLQuery(PtrTo<ClusterClause> cluster, PtrList list)
+            : Query(list), cluster_name(cluster ? cluster->convertToOld()->as<ASTLiteral>()->value.get<String>() : String{})
+        {
+        }
+
+        const String cluster_name;
+};
+
+}

src/Parsers/New/AST/DescribeQuery.cpp

@@ -0,0 +1,36 @@
+#include <Parsers/New/AST/DescribeQuery.h>
+
+#include <Parsers/TablePropertiesQueriesASTs.h>
+#include <Parsers/New/AST/TableExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+DescribeQuery::DescribeQuery(PtrTo<TableExpr> expr) : Query{expr}
+{
+}
+
+ASTPtr DescribeQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTDescribeQuery>();
+
+    query->table_expression = get(EXPR)->convertToOld();
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitDescribeStmt(ClickHouseParser::DescribeStmtContext *ctx)
+{
+    return std::make_shared<DescribeQuery>(visit(ctx->tableExpr()).as<PtrTo<TableExpr>>());
+}
+
+}

src/Parsers/New/AST/DescribeQuery.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+
+namespace DB::AST
+{
+
+// TODO: rewrite to
+//       `SELECT name, type, default_type, default_expression, comment, codec_expression, ttl_expression FROM system.columns
+//        WHERE database=db AND table=table`
+
+class DescribeQuery : public Query
+{
+    public:
+        explicit DescribeQuery(PtrTo<TableExpr> expr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            EXPR = 0,
+        };
+};
+
+}

src/Parsers/New/AST/DropQuery.cpp

@@ -0,0 +1,106 @@
+#include <Parsers/New/AST/DropQuery.h>
+
+#include <Parsers/New/AST/Identifier.h>
+
+#include <Parsers/New/ParseTreeVisitor.h>
+
+#include <Parsers/ASTDropQuery.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<DropQuery>
+DropQuery::createDropDatabase(bool detach, bool if_exists, PtrTo<DatabaseIdentifier> identifier, PtrTo<ClusterClause> cluster)
+{
+    auto query = PtrTo<DropQuery>(new DropQuery(cluster, QueryType::DATABASE, {identifier}));
+    query->detach = detach;
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<DropQuery>
+DropQuery::createDropDictionary(bool detach, bool if_exists, PtrTo<TableIdentifier> identifier, PtrTo<ClusterClause> cluster)
+{
+    auto query = PtrTo<DropQuery>(new DropQuery(cluster, QueryType::DICTIONARY, {identifier}));
+    query->detach = detach;
+    query->if_exists = if_exists;
+    return query;
+}
+
+// static
+PtrTo<DropQuery>
+DropQuery::createDropTable(bool detach, bool if_exists, bool temporary, PtrTo<TableIdentifier> identifier, PtrTo<ClusterClause> cluster)
+{
+    auto query = PtrTo<DropQuery>(new DropQuery(cluster, QueryType::TABLE, {identifier}));
+    query->detach = detach;
+    query->if_exists = if_exists;
+    query->temporary = temporary;
+    return query;
+}
+
+DropQuery::DropQuery(PtrTo<ClusterClause> cluster, QueryType type, PtrList exprs) : DDLQuery(cluster, exprs), query_type(type)
+{
+}
+
+ASTPtr DropQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTDropQuery>();
+
+    query->kind = detach ? ASTDropQuery::Detach : ASTDropQuery::Drop;
+    query->if_exists = if_exists;
+    query->temporary = temporary;
+    query->cluster = cluster_name;
+
+    // TODO: refactor |ASTQueryWithTableAndOutput| to accept |ASTIdentifier|
+    switch(query_type)
+    {
+        case QueryType::DATABASE:
+            query->database = get<DatabaseIdentifier>(NAME)->getName();
+            break;
+        case QueryType::DICTIONARY:
+            query->is_dictionary = true;
+            query->table = get<TableIdentifier>(NAME)->getName();
+            if (auto database = get<TableIdentifier>(NAME)->getDatabase())
+                query->database = database->getName();
+            break;
+        case QueryType::TABLE:
+        {
+            query->table = get<TableIdentifier>(NAME)->getName();
+            if (auto database = get<TableIdentifier>(NAME)->getDatabase())
+                query->database = database->getName();
+            break;
+        }
+    }
+
+    convertToOldPartially(query);
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitDropDatabaseStmt(ClickHouseParser::DropDatabaseStmtContext *ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    return DropQuery::createDropDatabase(!!ctx->DETACH(), !!ctx->EXISTS(), visit(ctx->databaseIdentifier()), cluster);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDropTableStmt(ClickHouseParser::DropTableStmtContext *ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    if (ctx->TABLE())
+        return DropQuery::createDropTable(!!ctx->DETACH(), !!ctx->EXISTS(), !!ctx->TEMPORARY(), visit(ctx->tableIdentifier()), cluster);
+    if (ctx->DICTIONARY())
+        return DropQuery::createDropDictionary(!!ctx->DETACH(), !!ctx->EXISTS(), visit(ctx->tableIdentifier()), cluster);
+    __builtin_unreachable();
+}
+
+}

src/Parsers/New/AST/DropQuery.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class DropQuery : public DDLQuery
+{
+    public:
+        static PtrTo<DropQuery>
+        createDropDatabase(bool detach, bool if_exists, PtrTo<DatabaseIdentifier> identifier, PtrTo<ClusterClause> cluster);
+        static PtrTo<DropQuery>
+        createDropTable(bool detach, bool if_exists, bool temporary, PtrTo<TableIdentifier> identifier, PtrTo<ClusterClause> cluster);
+        static PtrTo<DropQuery>
+        createDropDictionary(bool detach, bool if_exists, PtrTo<TableIdentifier> identifier, PtrTo<ClusterClause> cluster);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,
+        };
+
+        enum class QueryType
+        {
+            DATABASE,
+            DICTIONARY,
+            TABLE,
+        };
+
+        const QueryType query_type;
+
+        bool detach = false;
+        bool if_exists = false;
+        bool temporary = false;
+
+        DropQuery(PtrTo<ClusterClause> cluster, QueryType type, PtrList exprs);
+};
+
+}

src/Parsers/New/AST/EngineExpr.cpp

@@ -0,0 +1,199 @@
+#include <Parsers/New/AST/EngineExpr.h>
+
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/ASTTTLElement.h>
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+#include <Storages/DataDestinationType.h>
+#include <Storages/TTLMode.h>
+
+
+namespace DB::ErrorCodes
+{
+    extern const int UNEXPECTED_AST_STRUCTURE;
+}
+
+namespace DB::AST
+{
+
+EngineClause::EngineClause(PtrTo<EngineExpr> expr) : INode(MAX_INDEX)
+{
+    set(ENGINE, expr);
+}
+
+void EngineClause::setOrderByClause(PtrTo<OrderByClause> clause)
+{
+    set(ORDER_BY, clause);
+}
+
+void EngineClause::setPartitionByClause(PtrTo<PartitionByClause> clause)
+{
+    set(PARTITION_BY, clause);
+}
+
+void EngineClause::setPrimaryKeyClause(PtrTo<PrimaryKeyClause> clause)
+{
+    set(PRIMARY_KEY, clause);
+}
+
+void EngineClause::setSampleByClause(PtrTo<SampleByClause> clause)
+{
+    set(SAMPLE_BY, clause);
+}
+
+void EngineClause::setTTLClause(PtrTo<TTLClause> clause)
+{
+    set(TTL, clause);
+}
+
+void EngineClause::setSettingsClause(PtrTo<SettingsClause> clause)
+{
+    set(SETTINGS, clause);
+}
+
+ASTPtr EngineClause::convertToOld() const
+{
+    auto storage = std::make_shared<ASTStorage>();
+
+    storage->set(storage->engine, get(ENGINE)->convertToOld());
+    if (has(PARTITION_BY)) storage->set(storage->partition_by, get(PARTITION_BY)->convertToOld());
+    if (has(PRIMARY_KEY)) storage->set(storage->primary_key, get(PRIMARY_KEY)->convertToOld());
+    if (has(ORDER_BY))
+    {
+        /// XXX: old parser used very strange grammar for this case, instead of using OrderByElement's.
+        auto expr_list = get(ORDER_BY)->convertToOld();
+        if (expr_list->children.size() > 1)
+            throw DB::Exception(ErrorCodes::UNEXPECTED_AST_STRUCTURE, "Cannot convert multiple ORDER expression to old AST");
+        storage->set(storage->order_by, expr_list->children[0]->children[0]);
+    }
+    if (has(SAMPLE_BY)) storage->set(storage->sample_by, get(SAMPLE_BY)->convertToOld());
+    if (has(TTL)) storage->set(storage->ttl_table, get(TTL)->convertToOld());
+    if (has(SETTINGS))
+    {
+        storage->set(storage->settings, get(SETTINGS)->convertToOld());
+        storage->settings->is_standalone = false;
+    }
+
+    return storage;
+}
+
+EngineExpr::EngineExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExprList> args) : INode{identifier, args}
+{
+}
+
+ASTPtr EngineExpr::convertToOld() const
+{
+    auto expr = std::make_shared<ASTFunction>();
+
+    expr->name = get<Identifier>(NAME)->getName();
+    expr->no_empty_args = true;
+    if (has(ARGS))
+    {
+        expr->arguments = get(ARGS)->convertToOld();
+        expr->children.push_back(expr->arguments);
+    }
+
+    return expr;
+}
+
+TTLExpr::TTLExpr(PtrTo<ColumnExpr> expr, TTLType type, PtrTo<StringLiteral> literal) : INode{expr, literal}, ttl_type(type)
+{
+}
+
+ASTPtr TTLExpr::convertToOld() const
+{
+    TTLMode mode = TTLMode::DELETE;
+    DataDestinationType destination_type = DataDestinationType::DELETE;
+    String destination_name;
+
+    switch(ttl_type)
+    {
+        case TTLType::DELETE:
+            mode = TTLMode::DELETE;
+            destination_type = DataDestinationType::DELETE;
+            break;
+        case TTLType::TO_DISK:
+            mode = TTLMode::MOVE;
+            destination_type = DataDestinationType::DISK;
+            destination_name = get(TYPE)->convertToOld()->as<ASTLiteral>()->value.get<String>();
+            break;
+        case TTLType::TO_VOLUME:
+            mode = TTLMode::MOVE;
+            destination_type = DataDestinationType::VOLUME;
+            destination_name = get(TYPE)->convertToOld()->as<ASTLiteral>()->value.get<String>();
+            break;
+    }
+
+    auto expr = std::make_shared<ASTTTLElement>(mode, destination_type, destination_name);
+    expr->setTTL(get(EXPR)->convertToOld());
+    return expr;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitEngineClause(ClickHouseParser::EngineClauseContext *ctx)
+{
+    auto clause = std::make_shared<EngineClause>(visit(ctx->engineExpr()).as<PtrTo<EngineExpr>>());
+
+    if (!ctx->orderByClause().empty()) clause->setOrderByClause(visit(ctx->orderByClause(0)));
+    if (!ctx->partitionByClause().empty()) clause->setPartitionByClause(visit(ctx->partitionByClause(0)));
+    if (!ctx->primaryKeyClause().empty()) clause->setPrimaryKeyClause(visit(ctx->primaryKeyClause(0)));
+    if (!ctx->sampleByClause().empty()) clause->setSampleByClause(visit(ctx->sampleByClause(0)));
+    if (!ctx->ttlClause().empty()) clause->setTTLClause(visit(ctx->ttlClause(0)));
+    if (!ctx->settingsClause().empty()) clause->setSettingsClause(visit(ctx->settingsClause(0)));
+
+    return clause;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitEngineExpr(ClickHouseParser::EngineExprContext *ctx)
+{
+    auto list = ctx->columnExprList() ? visit(ctx->columnExprList()).as<PtrTo<ColumnExprList>>() : nullptr;
+    return std::make_shared<EngineExpr>(visit(ctx->identifierOrNull()), list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitPartitionByClause(ClickHouseParser::PartitionByClauseContext *ctx)
+{
+    return std::make_shared<PartitionByClause>(visit(ctx->columnExpr()).as<PtrTo<ColumnExpr>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitPrimaryKeyClause(ClickHouseParser::PrimaryKeyClauseContext *ctx)
+{
+    return std::make_shared<PrimaryKeyClause>(visit(ctx->columnExpr()).as<PtrTo<ColumnExpr>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSampleByClause(ClickHouseParser::SampleByClauseContext *ctx)
+{
+    return std::make_shared<SampleByClause>(visit(ctx->columnExpr()).as<PtrTo<ColumnExpr>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitTtlClause(ClickHouseParser::TtlClauseContext *ctx)
+{
+    auto list = std::make_shared<TTLExprList>();
+    for (auto * expr : ctx->ttlExpr()) list->push(visit(expr));
+    return std::make_shared<TTLClause>(list);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitTtlExpr(ClickHouseParser::TtlExprContext *ctx)
+{
+    TTLExpr::TTLType type;
+    PtrTo<StringLiteral> literal;
+
+    if (ctx->DISK()) type = TTLExpr::TTLType::TO_DISK;
+    else if (ctx->VOLUME()) type = TTLExpr::TTLType::TO_VOLUME;
+    else type = TTLExpr::TTLType::DELETE;
+
+    if (ctx->STRING_LITERAL()) literal = Literal::createString(ctx->STRING_LITERAL());
+
+    return std::make_shared<TTLExpr>(visit(ctx->columnExpr()), type, literal);
+}
+
+}

src/Parsers/New/AST/EngineExpr.h

@@ -0,0 +1,85 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+
+namespace DB::AST
+{
+
+// Clauses
+
+using PartitionByClause = SimpleClause<ColumnExpr>;
+
+using SampleByClause = SimpleClause<ColumnExpr>;
+
+class EngineClause : public INode
+{
+    public:
+        explicit EngineClause(PtrTo<EngineExpr> expr);
+
+        void setOrderByClause(PtrTo<OrderByClause> clause);
+        void setPartitionByClause(PtrTo<PartitionByClause> clause);
+        void setPrimaryKeyClause(PtrTo<PrimaryKeyClause> clause);
+        void setSampleByClause(PtrTo<SampleByClause> clause);
+        void setTTLClause(PtrTo<TTLClause> clause);
+        void setSettingsClause(PtrTo<SettingsClause> clause);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            ENGINE = 0,    // EngineExpr
+            ORDER_BY,      // OrderByClause (optional)
+            PARTITION_BY,  // PartitionByClause (optional)
+            PRIMARY_KEY,   // PrimaryKeyClause (optional)
+            SAMPLE_BY,     // SampleByClause (optional)
+            TTL,           // TTLClause (optional)
+            SETTINGS,      // SettingsClause (optional)
+
+            MAX_INDEX,
+        };
+};
+
+// Expressions
+
+class EngineExpr : public INode
+{
+    public:
+        EngineExpr(PtrTo<Identifier> identifier, PtrTo<ColumnExprList> args);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            NAME = 0,  // Identifier
+            ARGS,      // ColumnExprList (optional)
+        };
+};
+
+class TTLExpr : public INode
+{
+    public:
+        enum class TTLType
+        {
+            DELETE,
+            TO_DISK,
+            TO_VOLUME,
+        };
+
+        TTLExpr(PtrTo<ColumnExpr> expr, TTLType type, PtrTo<StringLiteral> literal);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            EXPR = 0,  // ColumnExpr
+            TYPE = 1,  // StringLiteral (optional)
+        };
+
+        TTLType ttl_type;
+};
+
+}

src/Parsers/New/AST/ExistsQuery.cpp

@@ -0,0 +1,55 @@
+#include <Parsers/New/AST/ExistsQuery.h>
+
+#include <Interpreters/StorageID.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+#include <Parsers/TablePropertiesQueriesASTs.h>
+
+
+namespace DB::AST
+{
+
+ExistsQuery::ExistsQuery(QueryType type, bool temporary_, PtrTo<TableIdentifier> identifier)
+    : Query{identifier}, query_type(type), temporary(temporary_)
+{
+}
+
+ASTPtr ExistsQuery::convertToOld() const
+{
+    std::shared_ptr<ASTQueryWithTableAndOutput> query;
+
+    switch(query_type)
+    {
+        case QueryType::DICTIONARY:
+            query = std::make_shared<ASTExistsDictionaryQuery>();
+            break;
+        case QueryType::TABLE:
+            query = std::make_shared<ASTExistsTableQuery>();
+            query->temporary = temporary;
+            break;
+    }
+
+    // FIXME: this won't work if table doesn't exist
+    auto table_id = getTableIdentifier(get(TABLE)->convertToOld());
+    query->database = table_id.database_name;
+    query->table = table_id.table_name;
+    query->uuid = table_id.uuid;
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitExistsStmt(ClickHouseParser::ExistsStmtContext *ctx)
+{
+    auto type = ctx->TABLE() ? ExistsQuery::QueryType::TABLE : ExistsQuery::QueryType::DICTIONARY;
+    return std::make_shared<ExistsQuery>(type, !!ctx->TEMPORARY(), visit(ctx->tableIdentifier()));
+}
+
+}

src/Parsers/New/AST/ExistsQuery.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+
+namespace DB::AST
+{
+
+class ExistsQuery : public Query
+{
+    public:
+        enum class QueryType
+        {
+            DICTIONARY,
+            TABLE,
+        };
+
+        ExistsQuery(QueryType type, bool temporary, PtrTo<TableIdentifier> identifier);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            TABLE = 0,  // TableIdentifier
+        };
+
+        const QueryType query_type;
+        const bool temporary;
+};
+
+}

src/Parsers/New/AST/ExplainQuery.cpp

@@ -0,0 +1,35 @@
+#include <Parsers/New/AST/ExplainQuery.h>
+
+#include <Parsers/ASTExplainQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+ExplainQuery::ExplainQuery(PtrTo<Query> query) : Query{query}
+{
+}
+
+ASTPtr ExplainQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTExplainQuery>(ASTExplainQuery::AnalyzedSyntax);
+
+    query->setExplainedQuery(get(QUERY)->convertToOld());
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace DB::AST;
+
+antlrcpp::Any ParseTreeVisitor::visitExplainStmt(ClickHouseParser::ExplainStmtContext *ctx)
+{
+    return std::make_shared<ExplainQuery>(visit(ctx->query()).as<PtrTo<Query>>());
+}
+
+}

src/Parsers/New/AST/ExplainQuery.h

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+
+namespace DB::AST
+{
+
+class ExplainQuery : public Query
+{
+    public:
+        explicit ExplainQuery(PtrTo<Query> query);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            QUERY = 0,  // Query
+        };
+};
+
+}

src/Parsers/New/AST/INode.h

@@ -0,0 +1,103 @@
+#pragma once
+
+#include <Parsers/New/AST/fwd_decl.h>
+
+#include <common/demangle.h>
+#include <Common/TypePromotion.h>
+#include <Parsers/ASTExpressionList.h>
+
+#include <initializer_list>
+#include <iostream>
+
+
+namespace DB::AST
+{
+
+class INode : public TypePromotion<INode>
+{
+    public:
+        virtual ~INode() = default;
+
+        virtual ASTPtr convertToOld() const { return ASTPtr(); }
+        virtual String toString() const { return {}; }
+
+        void dump() const { dump(0); }
+
+    protected:
+        INode() = default;
+        INode(std::initializer_list<Ptr> list) { children = list; }
+        explicit INode(PtrList list) { children = list; }
+        explicit INode(size_t size) { children.resize(size); }
+
+        void push(const Ptr& child) { children.push_back(child); }
+        void set(size_t i, const Ptr& child) { children[i] = child; }
+        bool has(size_t i) const { return i < children.size() && children[i]; }
+        const Ptr & get(size_t i) const { return children[i]; }
+
+        template <class ChildType>
+        bool has(size_t i) const { return has(i) && children[i]->as<ChildType>(); }
+
+        template <class ChildType>
+        ChildType * get(size_t i) const { return children[i]->template as<ChildType>(); }
+
+        auto begin() const { return children.cbegin(); }
+        auto end() const { return children.cend(); }
+        auto size() const { return children.size(); }
+
+    private:
+        PtrList children;  // any child potentially may point to |nullptr|
+
+        void dump(int indentation) const
+        {
+            for (auto i = 0; i < indentation; ++i) std::cout << " ";
+            std::cout << "⭸ " << demangle(typeid(*this).name()) << " (" << dumpInfo() << ")" << std::endl;
+            for (const auto & child : children) if (child) child->dump(indentation + 1);
+        }
+
+        virtual String dumpInfo() const { return ""; }
+};
+
+template <class T, char Separator>
+class List : public INode {
+    public:
+        List() = default;
+        List(std::initializer_list<PtrTo<T>> list)
+        {
+            for (const auto & i : list) push(i);
+        }
+
+        using INode::begin;
+        using INode::end;
+        using INode::size;
+
+        void push(const PtrTo<T> & node) { INode::push(node); }
+
+        ASTPtr convertToOld() const override
+        {
+            auto list = std::make_shared<ASTExpressionList>(Separator);
+            for (const auto & child : *this) list->children.emplace_back(child->convertToOld());
+            return list;
+        }
+
+        String toString() const override
+        {
+            if (!size()) return {};
+
+            auto string = (*begin())->toString();
+
+            for (auto next = ++begin(); next != end(); ++next)
+                string += String(1, Separator) + " " + (*next)->toString();
+
+            return string;
+        }
+};
+
+template <class T>
+class SimpleClause : public INode
+{
+    public:
+        explicit SimpleClause(PtrTo<T> expr) : INode{expr} {}
+        ASTPtr convertToOld() const override { return get(0)->convertToOld(); }
+};
+
+}

src/Parsers/New/AST/Identifier.cpp

@@ -0,0 +1,175 @@
+#include <Parsers/New/AST/Identifier.h>
+
+#include <IO/ReadHelpers.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+Identifier::Identifier(const String & name_) : name(name_)
+{
+    if (name.front() == '`' || name.front() == '"')
+    {
+        String s;
+        ReadBufferFromMemory in(name.data(), name.size());
+
+        if (name.front() == '`')
+            readBackQuotedStringWithSQLStyle(s, in);
+        else
+            readDoubleQuotedStringWithSQLStyle(s, in);
+
+        assert(in.count() == name.size());
+        name = s;
+    }
+}
+
+Identifier::Identifier(const String & name_, const String & nested_name) : name(name_ + "." + nested_name)
+{
+}
+
+ASTPtr Identifier::convertToOld() const
+{
+    return std::make_shared<ASTIdentifier>(getQualifiedName());
+}
+
+String Identifier::toString() const
+{
+    return getQualifiedName();
+}
+
+DatabaseIdentifier::DatabaseIdentifier(PtrTo<Identifier> name) : Identifier(*name)
+{
+}
+
+TableIdentifier::TableIdentifier(PtrTo<DatabaseIdentifier> database, PtrTo<Identifier> name) : Identifier(*name), db(database)
+{
+}
+
+void TableIdentifier::makeCompound() const
+{
+    if (db)
+    {
+        name = db->getName();
+        db.reset();
+    }
+}
+
+ASTPtr TableIdentifier::convertToOld() const
+{
+    std::vector<String> parts;
+
+    if (db && !db->getName().empty()) parts.push_back(db->getName());
+    parts.push_back(getName());
+
+    return std::make_shared<ASTIdentifier>(std::move(parts));
+}
+
+ColumnIdentifier::ColumnIdentifier(PtrTo<TableIdentifier> table_, PtrTo<Identifier> name) : Identifier(name->getName()), table(table_)
+{
+}
+
+void ColumnIdentifier::makeCompound() const
+{
+    if (table)
+    {
+        name = table->getName() + "." + getName();
+        if (table->getDatabase()) table->makeCompound();
+        else table.reset();
+    }
+}
+
+ASTPtr ColumnIdentifier::convertToOld() const
+{
+    std::vector<String> parts;
+
+    if (table)
+    {
+        if (table->getDatabase()) parts.push_back(table->getDatabase()->getName());
+        parts.push_back(table->getName());
+    }
+    parts.push_back(getName());
+
+    return std::make_shared<ASTIdentifier>(std::move(parts));
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitAlias(ClickHouseParser::AliasContext *ctx)
+{
+    if (ctx->IDENTIFIER()) return std::make_shared<Identifier>(ctx->IDENTIFIER()->getText());
+    if (ctx->keywordForAlias()) return std::make_shared<Identifier>(ctx->keywordForAlias()->getText());
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitColumnIdentifier(ClickHouseParser::ColumnIdentifierContext *ctx)
+{
+    auto table = ctx->tableIdentifier() ? visit(ctx->tableIdentifier()).as<PtrTo<TableIdentifier>>() : nullptr;
+    return std::make_shared<ColumnIdentifier>(table, visit(ctx->nestedIdentifier()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDatabaseIdentifier(ClickHouseParser::DatabaseIdentifierContext *ctx)
+{
+    return std::make_shared<DatabaseIdentifier>(visit(ctx->identifier()).as<PtrTo<Identifier>>());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitIdentifier(ClickHouseParser::IdentifierContext *ctx)
+{
+    if (ctx->IDENTIFIER()) return std::make_shared<Identifier>(ctx->IDENTIFIER()->getText());
+    if (ctx->interval()) return std::make_shared<Identifier>(ctx->interval()->getText());
+    if (ctx->keyword()) return std::make_shared<Identifier>(ctx->keyword()->getText());
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitIdentifierOrNull(ClickHouseParser::IdentifierOrNullContext *ctx)
+{
+    if (ctx->identifier()) return visit(ctx->identifier());
+    if (ctx->NULL_SQL())
+    {
+        if (ctx->NULL_SQL()->getSymbol()->getText() == "Null") return std::make_shared<Identifier>("Null");
+        else {
+            // TODO: raise error
+        }
+    }
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitInterval(ClickHouseParser::IntervalContext *)
+{
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitKeyword(ClickHouseParser::KeywordContext *)
+{
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitKeywordForAlias(ClickHouseParser::KeywordForAliasContext *)
+{
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitNestedIdentifier(ClickHouseParser::NestedIdentifierContext *ctx)
+{
+    if (ctx->identifier().size() == 2)
+    {
+        auto name1 = visit(ctx->identifier(0)).as<PtrTo<Identifier>>()->getName();
+        auto name2 = visit(ctx->identifier(1)).as<PtrTo<Identifier>>()->getName();
+        return std::make_shared<Identifier>(name1, name2);
+    }
+    else return visit(ctx->identifier(0));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitTableIdentifier(ClickHouseParser::TableIdentifierContext *ctx)
+{
+    auto database = ctx->databaseIdentifier() ? visit(ctx->databaseIdentifier()).as<PtrTo<DatabaseIdentifier>>() : nullptr;
+    return std::make_shared<TableIdentifier>(database, visit(ctx->identifier()));
+}
+
+}

src/Parsers/New/AST/Identifier.h

@@ -0,0 +1,66 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+
+namespace DB::AST
+{
+
+class Identifier : public INode
+{
+    public:
+        explicit Identifier(const String & name_);
+        Identifier(const String & name_, const String & nested_name);
+
+        const auto & getName() const { return name; }
+
+        ASTPtr convertToOld() const override;
+        String toString() const override;
+
+        virtual String getQualifiedName() const { return name; };
+
+    protected:
+        mutable String name; // protected and non-const because identifiers may become `column.nested` from `table.column`
+
+        String dumpInfo() const override { return getQualifiedName(); }
+};
+
+class DatabaseIdentifier : public Identifier
+{
+    public:
+        explicit DatabaseIdentifier(PtrTo<Identifier> name);
+};
+
+class TableIdentifier : public Identifier
+{
+    public:
+        TableIdentifier(PtrTo<DatabaseIdentifier> database, PtrTo<Identifier> name);
+
+        auto getDatabase() const { return db; }
+        void makeCompound() const;
+
+        String getQualifiedName() const override { return (db ? db->getQualifiedName() + "." : String()) + getName(); }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        mutable PtrTo<DatabaseIdentifier> db;
+};
+
+class ColumnIdentifier : public Identifier
+{
+    public:
+        ColumnIdentifier(PtrTo<TableIdentifier> table, PtrTo<Identifier> name);
+
+        auto getTable() const { return table; }
+        void makeCompound() const;
+
+        String getQualifiedName() const override { return (table ? table->getQualifiedName() + "." : String()) + getName(); }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        mutable PtrTo<TableIdentifier> table;
+};
+
+}

src/Parsers/New/AST/InsertQuery.cpp

@@ -0,0 +1,125 @@
+#include <Parsers/New/AST/InsertQuery.h>
+
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTInsertQuery.h>
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/SelectUnionQuery.h>
+#include <Parsers/New/AST/TableExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<DataClause> DataClause::createFormat(PtrTo<Identifier> identifier, size_t data_offset)
+{
+    PtrTo<DataClause> clause(new DataClause(ClauseType::FORMAT, {identifier}));
+    clause->offset = data_offset;
+    return clause;
+}
+
+// static
+PtrTo<DataClause> DataClause::createSelect(PtrTo<SelectUnionQuery> query)
+{
+    return PtrTo<DataClause>(new DataClause(ClauseType::SELECT, {query}));
+}
+
+// static
+PtrTo<DataClause> DataClause::createValues(size_t data_offset)
+{
+    PtrTo<DataClause> clause(new DataClause(ClauseType::VALUES, {}));
+    clause->offset = data_offset;
+    return clause;
+}
+
+DataClause::DataClause(ClauseType type, PtrList exprs) : INode(exprs), clause_type(type)
+{
+}
+
+ASTPtr DataClause::convertToOld() const
+{
+    if (clause_type != ClauseType::SELECT) return {};
+    return get(SUBQUERY)->convertToOld();
+}
+
+// static
+PtrTo<InsertQuery> InsertQuery::createTable(PtrTo<TableIdentifier> identifier, PtrTo<ColumnNameList> list, PtrTo<DataClause> clause)
+{
+    return PtrTo<InsertQuery>(new InsertQuery(QueryType::TABLE, {identifier, list, clause}));
+}
+
+// static
+PtrTo<InsertQuery> InsertQuery::createFunction(PtrTo<TableFunctionExpr> function, PtrTo<ColumnNameList> list, PtrTo<DataClause> clause)
+{
+    return PtrTo<InsertQuery>(new InsertQuery(QueryType::FUNCTION, {function, list, clause}));
+}
+
+InsertQuery::InsertQuery(QueryType type, PtrList exprs) : Query(exprs), query_type(type)
+{
+}
+
+ASTPtr InsertQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTInsertQuery>();
+
+    switch(query_type)
+    {
+        case QueryType::FUNCTION:
+            query->table_function = get(FUNCTION)->convertToOld();
+            break;
+        case QueryType::TABLE:
+            query->table_id = getTableIdentifier(get(IDENTIFIER)->convertToOld());
+            break;
+    }
+
+    if (has(COLUMNS)) query->columns = get(COLUMNS)->convertToOld();
+    if (get<DataClause>(DATA)->getType() == DataClause::ClauseType::SELECT)
+    {
+        query->select = get(DATA)->convertToOld();
+        query->children.push_back(query->select);
+    }
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitColumnsClause(ClickHouseParser::ColumnsClauseContext *ctx)
+{
+    auto list = std::make_shared<ColumnNameList>();
+    for (auto * name : ctx->nestedIdentifier()) list->push(visit(name));
+    return list;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDataClauseFormat(ClickHouseParser::DataClauseFormatContext *ctx)
+{
+    return DataClause::createFormat(visit(ctx->identifier()), ctx->getStop()->getStopIndex() + 1);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDataClauseSelect(ClickHouseParser::DataClauseSelectContext *ctx)
+{
+    return DataClause::createSelect(visit(ctx->selectUnionStmt()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitDataClauseValues(ClickHouseParser::DataClauseValuesContext *ctx)
+{
+    return DataClause::createValues(ctx->getStop()->getStopIndex() + 1);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitInsertStmt(ClickHouseParser::InsertStmtContext *ctx)
+{
+    auto columns = ctx->columnsClause() ? visit(ctx->columnsClause()).as<PtrTo<ColumnNameList>>() : nullptr;
+
+    if (ctx->FUNCTION()) return InsertQuery::createFunction(visit(ctx->tableFunctionExpr()), columns, visit(ctx->dataClause()));
+    if (ctx->tableIdentifier()) return InsertQuery::createTable(visit(ctx->tableIdentifier()), columns, visit(ctx->dataClause()));
+    __builtin_unreachable();
+}
+
+}

src/Parsers/New/AST/InsertQuery.h

@@ -0,0 +1,73 @@
+#pragma once
+
+#include <Parsers/New/AST/Query.h>
+
+
+namespace DB::AST
+{
+
+class DataClause : public INode
+{
+    public:
+        enum class ClauseType
+        {
+            FORMAT,
+            SELECT,
+            VALUES,
+        };
+
+        static PtrTo<DataClause> createFormat(PtrTo<Identifier> identifier, size_t data_offset);
+        static PtrTo<DataClause> createSelect(PtrTo<SelectUnionQuery> query);
+        static PtrTo<DataClause> createValues(size_t data_offset);
+
+        auto getType() const { return clause_type; }
+        auto getOffset() const { return offset; }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            FORMAT = 0,    // Identifier
+            SUBQUERY = 0,  // SelectUnionQuery
+        };
+
+        ClauseType clause_type;
+        size_t offset = 0;
+
+        DataClause(ClauseType type, PtrList exprs);
+};
+
+class InsertQuery : public Query
+{
+    public:
+        static PtrTo<InsertQuery> createFunction(PtrTo<TableFunctionExpr> function, PtrTo<ColumnNameList> list, PtrTo<DataClause> clause);
+        static PtrTo<InsertQuery> createTable(PtrTo<TableIdentifier> identifier, PtrTo<ColumnNameList> list, PtrTo<DataClause> clause);
+
+        bool hasData() const { return get<DataClause>(DATA)->getType() != DataClause::ClauseType::SELECT; }
+        size_t getDataOffset() const { return get<DataClause>(DATA)->getOffset(); }
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            IDENTIFIER = 0,  // TableIdentifier
+            FUNCTION = 0,    // TableFunctionExpr
+            COLUMNS = 1,     // ColumnNameList
+            DATA = 2,        // DataClause
+        };
+        enum class QueryType
+        {
+            FUNCTION,
+            TABLE,
+        };
+
+        QueryType query_type;
+
+        InsertQuery(QueryType type, PtrList exprs);
+
+        String dumpInfo() const override { return String("has_data=") + (hasData() ? "true" : "false"); }
+};
+
+}

src/Parsers/New/AST/JoinExpr.cpp

@@ -0,0 +1,326 @@
+#include <Parsers/New/AST/JoinExpr.h>
+
+#include <Parsers/ASTExpressionList.h>
+#include <Parsers/ASTTablesInSelectQuery.h>
+#include <Parsers/New/AST/RatioExpr.h>
+#include <Parsers/New/AST/TableExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::ErrorCodes
+{
+    extern const int UNEXPECTED_AST_STRUCTURE;
+}
+
+namespace DB::AST
+{
+
+JoinConstraintClause::JoinConstraintClause(ConstraintType type_, PtrTo<ColumnExprList> list) : SimpleClause{list}, type(type_)
+{
+}
+
+SampleClause::SampleClause(PtrTo<RatioExpr> ratio, PtrTo<RatioExpr> offset) : INode{ratio, offset}
+{
+}
+
+ASTPtr SampleClause::convertToOld() const
+{
+    auto list = std::make_shared<ASTExpressionList>();
+
+    list->children.push_back(get(RATIO)->convertToOld());
+    if (has(OFFSET)) list->children.push_back(get(OFFSET)->convertToOld());
+
+    return list;
+}
+
+// static
+PtrTo<JoinExpr> JoinExpr::createTableExpr(PtrTo<TableExpr> expr, PtrTo<SampleClause> clause, bool final)
+{
+    return PtrTo<JoinExpr>(new JoinExpr(JoinExpr::ExprType::TABLE, final, {expr, clause}));
+}
+
+// static
+PtrTo<JoinExpr> JoinExpr::createJoinOp(
+    PtrTo<JoinExpr> left_expr, PtrTo<JoinExpr> right_expr, JoinOpType op, JoinOpMode mode, PtrTo<JoinConstraintClause> clause)
+{
+    return PtrTo<JoinExpr>(new JoinExpr(ExprType::JOIN_OP, op, mode, {left_expr, right_expr, clause}));
+}
+
+JoinExpr::JoinExpr(JoinExpr::ExprType type, bool final_, PtrList exprs) : INode(exprs), expr_type(type), final(final_)
+{
+}
+
+JoinExpr::JoinExpr(JoinExpr::ExprType type, JoinExpr::JoinOpType op, JoinExpr::JoinOpMode mode, PtrList exprs)
+    : INode(exprs), expr_type(type), op_type(op), op_mode(mode)
+{
+}
+
+ASTPtr JoinExpr::convertToOld() const
+{
+    /** The sole convertable chain of Join's may look like:
+     *
+     *      … FROM table1 JOIN table2 ON SMTH JOIN table3 ON SMTH JOIN …
+     *
+     *  Since Join is a left-associative operation then the tree will look like:
+     *
+     *                JoinExpr
+     *               /       \
+     *           JoinExpr     …
+     *          /       \
+     *      JoinExpr   table3
+     *     /       \
+     *  table1    table2
+     *
+     *  To linearize this tree we have to start from the top-most expression.
+     */
+
+    auto list = std::make_shared<ASTExpressionList>();
+
+    if (expr_type == ExprType::TABLE)
+    {
+        auto element = std::make_shared<ASTTablesInSelectQueryElement>();
+        element->children.emplace_back(get(TABLE)->convertToOld());
+        element->table_expression = element->children.back();
+        element->table_expression->as<ASTTableExpression>()->final = final;
+        if (has(SAMPLE))
+        {
+            auto old_list = get(SAMPLE)->convertToOld();
+
+            element->table_expression->as<ASTTableExpression>()->sample_size = old_list->children[0];
+            element->table_expression->children.push_back(element->table_expression->as<ASTTableExpression>()->sample_size);
+
+            if (old_list->children.size() > 1)
+            {
+                element->table_expression->as<ASTTableExpression>()->sample_offset = old_list->children[1];
+                element->table_expression->children.push_back(element->table_expression->as<ASTTableExpression>()->sample_offset);
+            }
+        }
+
+        list->children.emplace_back(element);
+    }
+    else if (expr_type == ExprType::JOIN_OP)
+    {
+        if (get<JoinExpr>(RIGHT_EXPR)->expr_type != ExprType::TABLE)
+            throw Exception(ErrorCodes::UNEXPECTED_AST_STRUCTURE, "Cannot convert new tree-like JoinExpr to old AST");
+
+        auto left = get(LEFT_EXPR)->convertToOld(), right = get(RIGHT_EXPR)->convertToOld();  // ASTExpressionList's
+        list->children.insert(list->children.end(), left->children.begin(), left->children.end());  // Insert all the previously parsed left subtree
+        list->children.emplace_back(right->children[0]);  // Insert only first (single) ASTTablesInSelectQueryElement which should contain only ASTTableExpression
+
+        auto element = std::make_shared<ASTTableJoin>();
+        switch (op_mode)
+        {
+            case JoinOpMode::DEFAULT:
+                element->locality = ASTTableJoin::Locality::Unspecified;
+                break;
+            case JoinOpMode::GLOBAL:
+                element->locality = ASTTableJoin::Locality::Global;
+                break;
+            case JoinOpMode::LOCAL:
+                element->locality = ASTTableJoin::Locality::Local;
+                break;
+        }
+        switch (op_type)
+        {
+            case JoinOpType::CROSS:
+                element->kind = ASTTableJoin::Kind::Cross;
+                break;
+            case JoinOpType::FULL:
+                element->kind = ASTTableJoin::Kind::Full;
+                break;
+            case JoinOpType::FULL_ALL:
+                element->kind = ASTTableJoin::Kind::Full;
+                element->strictness = ASTTableJoin::Strictness::All;
+                break;
+            case JoinOpType::FULL_ANY:
+                element->kind = ASTTableJoin::Kind::Full;
+                element->strictness = ASTTableJoin::Strictness::Any;
+                break;
+            case JoinOpType::INNER:
+                element->kind = ASTTableJoin::Kind::Inner;
+                break;
+            case JoinOpType::INNER_ALL:
+                element->kind = ASTTableJoin::Kind::Inner;
+                element->strictness = ASTTableJoin::Strictness::All;
+                break;
+            case JoinOpType::INNER_ANY:
+                element->kind = ASTTableJoin::Kind::Inner;
+                element->strictness = ASTTableJoin::Strictness::Any;
+                break;
+            case JoinOpType::INNER_ASOF:
+                element->kind = ASTTableJoin::Kind::Inner;
+                element->strictness = ASTTableJoin::Strictness::Asof;
+                break;
+            case JoinOpType::LEFT:
+                element->kind = ASTTableJoin::Kind::Left;
+                break;
+            case JoinOpType::LEFT_ALL:
+                element->kind = ASTTableJoin::Kind::Left;
+                element->strictness = ASTTableJoin::Strictness::All;
+                break;
+            case JoinOpType::LEFT_ANTI:
+                element->kind = ASTTableJoin::Kind::Left;
+                element->strictness = ASTTableJoin::Strictness::Anti;
+                break;
+            case JoinOpType::LEFT_ANY:
+                element->kind = ASTTableJoin::Kind::Left;
+                element->strictness = ASTTableJoin::Strictness::Any;
+                break;
+            case JoinOpType::LEFT_ASOF:
+                element->kind = ASTTableJoin::Kind::Left;
+                element->strictness = ASTTableJoin::Strictness::Asof;
+                break;
+            case JoinOpType::LEFT_SEMI:
+                element->kind = ASTTableJoin::Kind::Left;
+                element->strictness = ASTTableJoin::Strictness::Semi;
+                break;
+            case JoinOpType::RIGHT:
+                element->kind = ASTTableJoin::Kind::Right;
+                break;
+            case JoinOpType::RIGHT_ANTI:
+                element->kind = ASTTableJoin::Kind::Right;
+                element->strictness = ASTTableJoin::Strictness::Anti;
+                break;
+            case JoinOpType::RIGHT_ALL:
+                element->kind = ASTTableJoin::Kind::Right;
+                element->strictness = ASTTableJoin::Strictness::All;
+                break;
+            case JoinOpType::RIGHT_ANY:
+                element->kind = ASTTableJoin::Kind::Right;
+                element->strictness = ASTTableJoin::Strictness::Any;
+                break;
+            case JoinOpType::RIGHT_ASOF:
+                element->kind = ASTTableJoin::Kind::Right;
+                element->strictness = ASTTableJoin::Strictness::Asof;
+                break;
+            case JoinOpType::RIGHT_SEMI:
+                element->kind = ASTTableJoin::Kind::Right;
+                element->strictness = ASTTableJoin::Strictness::Semi;
+                break;
+        }
+
+        if (has(CONSTRAINT))
+        {
+            const auto * constraint = get<JoinConstraintClause>(CONSTRAINT);
+            switch(constraint->getType())
+            {
+                case JoinConstraintClause::ConstraintType::ON:
+                    element->on_expression = constraint->convertToOld();
+                    if (element->on_expression->children.size() > 1)
+                        throw Exception(ErrorCodes::UNEXPECTED_AST_STRUCTURE, "Cannot convert JoinExpr with more than one ON expression");
+                    element->on_expression = element->on_expression->children[0];
+                    element->children.push_back(element->on_expression);
+                    break;
+                case JoinConstraintClause::ConstraintType::USING:
+                    element->using_expression_list = constraint->convertToOld();
+                    element->children.push_back(element->using_expression_list);
+                    break;
+            }
+        }
+
+        list->children.back()->children.emplace_back(element);
+        list->children.back()->as<ASTTablesInSelectQueryElement>()->table_join = element;
+    }
+
+    return list;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitJoinConstraintClause(ClickHouseParser::JoinConstraintClauseContext *ctx)
+{
+    return std::make_shared<JoinConstraintClause>(
+        ctx->ON() ? JoinConstraintClause::ConstraintType::ON : JoinConstraintClause::ConstraintType::USING,
+        visit(ctx->columnExprList()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinExprCrossOp(ClickHouseParser::JoinExprCrossOpContext *ctx)
+{
+    auto [op, mode] = std::pair<JoinExpr::JoinOpType, JoinExpr::JoinOpMode>(visit(ctx->joinOpCross()));
+
+    return JoinExpr::createJoinOp(visit(ctx->joinExpr(0)), visit(ctx->joinExpr(1)), op, mode, nullptr);
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinExprOp(ClickHouseParser::JoinExprOpContext *ctx)
+{
+    auto mode = JoinExpr::JoinOpMode::DEFAULT;
+    auto op = ctx->joinOp() ? visit(ctx->joinOp()).as<JoinExpr::JoinOpType>() : JoinExpr::JoinOpType::INNER;
+
+    if (ctx->GLOBAL()) mode = JoinExpr::JoinOpMode::GLOBAL;
+    else if (ctx->LOCAL()) mode = JoinExpr::JoinOpMode::LOCAL;
+
+    return JoinExpr::createJoinOp(visit(ctx->joinExpr(0)), visit(ctx->joinExpr(1)), op, mode, visit(ctx->joinConstraintClause()));
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinExprParens(ClickHouseParser::JoinExprParensContext *ctx)
+{
+    return visit(ctx->joinExpr());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinExprTable(ClickHouseParser::JoinExprTableContext *ctx)
+{
+    auto sample = ctx->sampleClause() ? visit(ctx->sampleClause()).as<PtrTo<SampleClause>>() : nullptr;
+    return JoinExpr::createTableExpr(visit(ctx->tableExpr()), sample, !!ctx->FINAL());
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinOpCross(ClickHouseParser::JoinOpCrossContext *ctx)
+{
+    std::pair<JoinExpr::JoinOpType, JoinExpr::JoinOpMode> op{
+        JoinExpr::JoinOpType::CROSS, JoinExpr::JoinOpMode::DEFAULT};
+
+    if (ctx->GLOBAL()) op.second = JoinExpr::JoinOpMode::GLOBAL;
+    else if (ctx->LOCAL()) op.second = JoinExpr::JoinOpMode::LOCAL;
+
+    return op;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinOpFull(ClickHouseParser::JoinOpFullContext *ctx)
+{
+    if (ctx->ALL()) return JoinExpr::JoinOpType::FULL_ALL;
+    if (ctx->ANY()) return JoinExpr::JoinOpType::FULL_ANY;
+    return JoinExpr::JoinOpType::FULL;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinOpInner(ClickHouseParser::JoinOpInnerContext *ctx)
+{
+    if (ctx->ALL()) return JoinExpr::JoinOpType::INNER_ALL;
+    if (ctx->ANY()) return JoinExpr::JoinOpType::INNER_ANY;
+    if (ctx->ASOF()) return JoinExpr::JoinOpType::INNER_ASOF;
+    return JoinExpr::JoinOpType::INNER;
+}
+
+antlrcpp::Any ParseTreeVisitor::visitJoinOpLeftRight(ClickHouseParser::JoinOpLeftRightContext *ctx)
+{
+    if (ctx->LEFT())
+    {
+        if (ctx->SEMI()) return JoinExpr::JoinOpType::LEFT_SEMI;
+        if (ctx->ALL()) return JoinExpr::JoinOpType::LEFT_ALL;
+        if (ctx->ANTI()) return JoinExpr::JoinOpType::LEFT_ANTI;
+        if (ctx->ANY()) return JoinExpr::JoinOpType::LEFT_ANY;
+        if (ctx->ASOF()) return JoinExpr::JoinOpType::LEFT_ASOF;
+        return JoinExpr::JoinOpType::LEFT;
+    }
+    else if (ctx->RIGHT())
+    {
+        if (ctx->SEMI()) return JoinExpr::JoinOpType::RIGHT_SEMI;
+        if (ctx->ALL()) return JoinExpr::JoinOpType::RIGHT_ALL;
+        if (ctx->ANTI()) return JoinExpr::JoinOpType::RIGHT_ANTI;
+        if (ctx->ANY()) return JoinExpr::JoinOpType::RIGHT_ANY;
+        if (ctx->ASOF()) return JoinExpr::JoinOpType::RIGHT_ASOF;
+        return JoinExpr::JoinOpType::RIGHT;
+    }
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitSampleClause(ClickHouseParser::SampleClauseContext *ctx)
+{
+    auto offset = ctx->ratioExpr().size() == 2 ? visit(ctx->ratioExpr(1)).as<PtrTo<RatioExpr>>() : nullptr;
+    return std::make_shared<SampleClause>(visit(ctx->ratioExpr(0)), offset);
+}
+
+}

src/Parsers/New/AST/JoinExpr.h

@@ -0,0 +1,103 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+
+namespace DB::AST
+{
+
+class JoinConstraintClause : public SimpleClause<ColumnExprList>
+{
+    public:
+        enum class ConstraintType
+        {
+            ON,
+            USING,
+        };
+
+        JoinConstraintClause(ConstraintType type, PtrTo<ColumnExprList> list);
+
+        auto getType() const { return type; }
+
+    private:
+        const ConstraintType type;
+};
+
+class SampleClause : public INode
+{
+    public:
+        SampleClause(PtrTo<RatioExpr> ratio_, PtrTo<RatioExpr> offset_);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            RATIO = 0,   // RatioExpr
+            OFFSET = 1,  // RatioExpr (optional)
+        };
+};
+
+class JoinExpr : public INode
+{
+    public:
+        enum class JoinOpType
+        {
+            INNER,
+            INNER_ALL,
+            INNER_ANY,
+            INNER_ASOF,
+            LEFT,
+            LEFT_SEMI,
+            LEFT_ALL,
+            LEFT_ANTI,
+            LEFT_ANY,
+            LEFT_ASOF,
+            RIGHT,
+            RIGHT_SEMI,
+            RIGHT_ALL,
+            RIGHT_ANTI,
+            RIGHT_ANY,
+            RIGHT_ASOF,
+            FULL,
+            FULL_ALL,
+            FULL_ANY,
+            CROSS,
+        };
+        enum class JoinOpMode
+        {
+            DEFAULT,  // actual mode depends on setting's 'distributed_product_mode' value
+            GLOBAL,
+            LOCAL,
+        };
+
+        static PtrTo<JoinExpr> createTableExpr(PtrTo<TableExpr> expr, PtrTo<SampleClause> clause, bool final);
+        static PtrTo<JoinExpr> createJoinOp(PtrTo<JoinExpr> left_expr, PtrTo<JoinExpr> right_expr, JoinOpType op, JoinOpMode mode, PtrTo<JoinConstraintClause> clause);
+
+        ASTPtr convertToOld() const override;  // returns topologically sorted elements as ASTExpressionList
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            TABLE = 0,       // TableExpr
+            SAMPLE = 1,      // SampleClause (optional)
+            LEFT_EXPR = 0,   // JoinExpr
+            RIGHT_EXPR = 1,  // JoinExpr
+            CONSTRAINT = 2,  // JoinConstraintClause
+        };
+        enum class ExprType
+        {
+            TABLE,
+            JOIN_OP,
+        };
+
+        const ExprType expr_type;
+        const JoinOpType op_type = JoinOpType::INNER;
+        const JoinOpMode op_mode = JoinOpMode::DEFAULT;
+        const bool final = false;
+
+        JoinExpr(ExprType type, bool final, PtrList exprs);
+        JoinExpr(ExprType type, JoinOpType op, JoinOpMode mode, PtrList exprs);
+};
+
+}

src/Parsers/New/AST/KillQuery.cpp

@@ -0,0 +1,56 @@
+#include <Parsers/New/AST/KillQuery.h>
+
+#include <Parsers/ASTKillQueryQuery.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<KillQuery> KillQuery::createMutation(PtrTo<ClusterClause> cluster, bool sync, bool test, PtrTo<WhereClause> where)
+{
+    PtrTo<KillQuery> query(new KillQuery(cluster, QueryType::MUTATION, {where}));
+    query->sync = sync;
+    query->test = test;
+    return query;
+}
+
+KillQuery::KillQuery(PtrTo<ClusterClause> cluster, QueryType type, PtrList exprs) : DDLQuery(cluster, exprs), query_type(type)
+{
+}
+
+ASTPtr KillQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTKillQueryQuery>();
+
+    query->cluster = cluster_name;
+
+    switch(query_type)
+    {
+        case QueryType::MUTATION:
+            query->type = ASTKillQueryQuery::Type::Mutation;
+            query->sync = sync;
+            query->test = test;
+            query->where_expression = get(WHERE)->convertToOld();
+            query->children.push_back(query->where_expression);
+            break;
+    }
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitKillMutationStmt(ClickHouseParser::KillMutationStmtContext * ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    return KillQuery::createMutation(cluster, !!ctx->SYNC(), !!ctx->TEST(), visit(ctx->whereClause()));
+}
+
+}

src/Parsers/New/AST/KillQuery.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <Parsers/New/AST/DDLQuery.h>
+
+
+namespace DB::AST
+{
+
+class KillQuery : public DDLQuery
+{
+    public:
+        static PtrTo<KillQuery> createMutation(PtrTo<ClusterClause> cluster, bool sync, bool test, PtrTo<WhereClause> where);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            WHERE = 0,  // WhereClause
+        };
+
+        enum class QueryType
+        {
+            MUTATION,
+        };
+
+        const QueryType query_type;
+        bool sync = false, test = false;
+
+        KillQuery(PtrTo<ClusterClause> cluster, QueryType type, PtrList exprs);
+};
+
+}

src/Parsers/New/AST/LimitExpr.cpp

@@ -0,0 +1,39 @@
+#include <Parsers/New/AST/LimitExpr.h>
+
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+LimitExpr::LimitExpr(PtrTo<ColumnExpr> limit, PtrTo<ColumnExpr> offset) : INode{limit, offset}
+{
+}
+
+ASTPtr LimitExpr::convertToOld() const
+{
+    auto list = std::make_shared<ASTExpressionList>();
+
+    if (has(OFFSET)) list->children.push_back(get(OFFSET)->convertToOld());
+    list->children.push_back(get(LIMIT)->convertToOld());
+
+    return list;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitLimitExpr(ClickHouseParser::LimitExprContext *ctx)
+{
+    if (ctx->columnExpr().size() == 2)
+        return std::make_shared<LimitExpr>(visit(ctx->columnExpr(0)), visit(ctx->columnExpr(1)));
+    else
+        return std::make_shared<LimitExpr>(visit(ctx->columnExpr(0)).as<PtrTo<ColumnExpr>>());
+}
+
+}

src/Parsers/New/AST/LimitExpr.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+
+namespace DB::AST
+{
+
+class LimitExpr : public INode
+{
+    public:
+        explicit LimitExpr(PtrTo<ColumnExpr> limit, PtrTo<ColumnExpr> offset = nullptr);
+
+        ASTPtr convertToOld() const override;
+
+    private:
+        enum ChildIndex : UInt8
+        {
+            LIMIT = 0,   // ColumnExpr
+            OFFSET = 1,  // ColumnExpr (optional)
+        };
+};
+
+}

src/Parsers/New/AST/Literal.cpp

@@ -0,0 +1,222 @@
+#include <Parsers/New/AST/Literal.h>
+
+#include <IO/ReadHelpers.h>
+#include <IO/WriteBufferFromString.h>
+#include <IO/WriteHelpers.h>
+#include <Parsers/ASTLiteral.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+// static
+PtrTo<Literal> Literal::createNull()
+{
+    return PtrTo<Literal>(new Literal(LiteralType::NULL_LITERAL, String()));
+}
+
+// static
+PtrTo<NumberLiteral> Literal::createNumber(antlr4::tree::TerminalNode * literal, bool negative)
+{
+    auto number = std::make_shared<NumberLiteral>(literal);
+    if (negative) number->makeNegative();
+    return number;
+}
+
+// static
+PtrTo<NumberLiteral> Literal::createNumber(const String & literal)
+{
+    bool has_minus = literal[0] == '-';
+    auto number = std::make_shared<NumberLiteral>(has_minus ? literal.substr(1) : literal);
+    if (has_minus) number->makeNegative();
+    return number;
+}
+
+// static
+PtrTo<StringLiteral> Literal::createString(antlr4::tree::TerminalNode * literal)
+{
+    return std::make_shared<StringLiteral>(literal);
+}
+
+// static
+PtrTo<StringLiteral> Literal::createString(const String & literal)
+{
+    return std::make_shared<StringLiteral>(literal);
+}
+
+Literal::Literal(LiteralType type_, const String & token_) : token(token_), type(type_)
+{
+}
+
+ASTPtr Literal::convertToOld() const
+{
+    auto as_field = [this] () -> Field
+    {
+        switch(type)
+        {
+            case LiteralType::NULL_LITERAL:
+                return Field(Null());
+            case LiteralType::NUMBER:
+            {
+                const auto * number = this->as<NumberLiteral>();
+
+                if (!number->isNegative())
+                    if (auto value = number->as<UInt64>()) return Field(*value);
+                if (auto value = number->as<Int64>()) return Field(*value);
+                if (auto value = number->as<Float64>()) return Field(*value);
+
+                return Field();
+            }
+            case LiteralType::STRING:
+                return asString();
+        }
+        __builtin_unreachable();
+    };
+
+    return std::make_shared<ASTLiteral>(as_field());
+}
+
+String Literal::toString() const
+{
+    WriteBufferFromOwnString wb;
+    writeEscapedString(token, wb);
+    return type == LiteralType::STRING ? "'" + wb.str() + "'" : wb.str();
+}
+
+NumberLiteral::NumberLiteral(antlr4::tree::TerminalNode * literal) : Literal(LiteralType::NUMBER, literal->getSymbol()->getText())
+{
+}
+
+NumberLiteral::NumberLiteral(const String & literal) : Literal(LiteralType::NUMBER, literal)
+{
+}
+
+String NumberLiteral::toString() const
+{
+    return (minus ? String("-") : String()) + Literal::toString();
+}
+
+ASTSampleRatio::Rational NumberLiteral::convertToOldRational() const
+{
+    UInt64 num_before = 0;
+    UInt64 num_after = 0;
+    Int64 exponent = 0;
+
+    const char * pos = token.data(), * end = token.data() + token.size();
+    const char * pos_after_first_num = tryReadIntText(num_before, pos, end);
+
+    bool has_num_before_point [[maybe_unused]] = pos_after_first_num > pos;
+    pos = pos_after_first_num;
+    bool has_point = pos < end && *pos == '.';
+
+    if (has_point)
+        ++pos;
+
+    assert (has_num_before_point || has_point);
+
+    size_t number_of_digits_after_point = 0;
+
+    if (has_point)
+    {
+        const char * pos_after_second_num = tryReadIntText(num_after, pos, end);
+        number_of_digits_after_point = pos_after_second_num - pos;
+        pos = pos_after_second_num;
+    }
+
+    bool has_exponent = pos < end && (*pos == 'e' || *pos == 'E');
+
+    if (has_exponent)
+    {
+        ++pos;
+        const char * pos_after_exponent [[maybe_unused]] = tryReadIntText(exponent, pos, end);
+        assert (pos_after_exponent != pos);
+    }
+
+    ASTSampleRatio::Rational res;
+    res.numerator = num_before * intExp10(number_of_digits_after_point) + num_after;
+    res.denominator = intExp10(number_of_digits_after_point);
+
+    if (exponent > 0)
+        res.numerator *= intExp10(exponent);
+    if (exponent < 0)
+        res.denominator *= intExp10(-exponent);
+
+    return res;
+}
+
+StringLiteral::StringLiteral(antlr4::tree::TerminalNode * literal) : Literal(LiteralType::STRING, literal->getSymbol()->getText())
+{
+    String s;
+    ReadBufferFromMemory in(token.data(), token.size());
+
+    readQuotedStringWithSQLStyle(s, in);
+
+    assert(in.count() == token.size());
+    token = s;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitFloatingLiteral(ClickHouseParser::FloatingLiteralContext * ctx)
+{
+    if (ctx->FLOATING_LITERAL()) return Literal::createNumber(ctx->FLOATING_LITERAL());
+
+    const auto * dot = ctx->DOT()->getSymbol();
+
+    if (!ctx->DECIMAL_LITERAL().empty())
+    {
+        // .1234
+        if (dot->getTokenIndex() < ctx->DECIMAL_LITERAL(0)->getSymbol()->getTokenIndex())
+            return Literal::createNumber(dot->getText() + ctx->DECIMAL_LITERAL(0)->getSymbol()->getText());
+        // 1234.
+        else if (ctx->DECIMAL_LITERAL().size() == 1 && !ctx->OCTAL_LITERAL())
+            return Literal::createNumber(ctx->DECIMAL_LITERAL(0)->getSymbol()->getText() + dot->getText());
+        // 1234.1234
+        else if (ctx->DECIMAL_LITERAL().size() == 2)
+            return Literal::createNumber(
+                ctx->DECIMAL_LITERAL(0)->getSymbol()->getText() + dot->getText() + ctx->DECIMAL_LITERAL(1)->getSymbol()->getText());
+        // 1234.0123
+        else
+            return Literal::createNumber(
+                ctx->DECIMAL_LITERAL(0)->getSymbol()->getText() + dot->getText() + ctx->OCTAL_LITERAL()->getSymbol()->getText());
+    }
+    else
+        // .0123
+        return Literal::createNumber(dot->getText() + ctx->OCTAL_LITERAL()->getSymbol()->getText());
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitLiteral(ClickHouseParser::LiteralContext * ctx)
+{
+    if (ctx->NULL_SQL())
+        return Literal::createNull();
+    if (ctx->STRING_LITERAL())
+        return std::static_pointer_cast<Literal>(Literal::createString(ctx->STRING_LITERAL()));
+    if (ctx->numberLiteral())
+        return std::static_pointer_cast<Literal>(visit(ctx->numberLiteral()).as<PtrTo<NumberLiteral>>());
+    __builtin_unreachable();
+}
+
+antlrcpp::Any ParseTreeVisitor::visitNumberLiteral(ClickHouseParser::NumberLiteralContext *ctx)
+{
+    if (ctx->floatingLiteral())
+    {
+        auto number = visit(ctx->floatingLiteral()).as<PtrTo<NumberLiteral>>();
+        if (ctx->DASH()) number->makeNegative();
+        return number;
+    }
+    if (ctx->OCTAL_LITERAL()) return Literal::createNumber(ctx->OCTAL_LITERAL(), !!ctx->DASH());
+    if (ctx->DECIMAL_LITERAL()) return Literal::createNumber(ctx->DECIMAL_LITERAL(), !!ctx->DASH());
+    if (ctx->HEXADECIMAL_LITERAL()) return Literal::createNumber(ctx->HEXADECIMAL_LITERAL(), !!ctx->DASH());
+    if (ctx->INF()) return Literal::createNumber(ctx->INF(), !!ctx->DASH());
+    if (ctx->NAN_SQL()) return Literal::createNumber(ctx->NAN_SQL());
+    __builtin_unreachable();
+}
+
+}

src/Parsers/New/AST/Literal.h

@@ -0,0 +1,96 @@
+#pragma once
+
+#include <Parsers/New/AST/INode.h>
+
+#include <Core/Field.h>
+#include <Parsers/ASTSampleRatio.h>
+
+#include <Token.h>
+#include <tree/TerminalNode.h>
+
+#include <sstream>
+
+
+namespace DB::AST
+{
+
+class Literal : public INode
+{
+    public:
+        enum class LiteralType
+        {
+            NULL_LITERAL,
+            NUMBER,
+            STRING,
+        };
+
+        static PtrTo<Literal> createNull();
+        static PtrTo<NumberLiteral> createNumber(antlr4::tree::TerminalNode * literal, bool negative = false);
+        static PtrTo<NumberLiteral> createNumber(const String& literal); // checks first symbol for '-' character
+        static PtrTo<StringLiteral> createString(antlr4::tree::TerminalNode * literal);
+        static PtrTo<StringLiteral> createString(const String& literal); // without quotes
+
+        ASTPtr convertToOld() const override;
+        String toString() const override;
+
+        bool is(LiteralType what) const { return type == what; }
+
+    protected:
+        String token; // STRING is stored without quotes and interpolated with escape-sequences.
+
+        Literal(LiteralType type, const String & token);
+
+        template <typename T>
+        std::optional<T> asNumber(bool minus) const
+        {
+            T number;
+            std::stringstream ss(String(minus ? "-" : "+") + token);
+            if (token.size() > 2 && (token[1] == 'x' || token[1] == 'X')) ss >> std::hex >> number;
+            else if (token.size() > 1 && (token[0] == '0')) ss >> std::oct >> number;
+            else ss >> number;
+            if (ss.fail() || !ss.eof())
+                return {};
+            return number;
+        }
+
+        auto asString() const { return token; }
+
+    private:
+        LiteralType type;
+
+        String dumpInfo() const override { return token; }
+};
+
+class NumberLiteral : public Literal
+{
+    public:
+        explicit NumberLiteral(antlr4::tree::TerminalNode * literal);
+        explicit NumberLiteral(const String & literal);
+
+        String toString() const override;
+
+        void makeNegative() { minus = true; }
+        bool isNegative() const { return minus; }
+
+        template <typename T> std::optional<T> as() const { return asNumber<T>(minus); }
+
+        ASTSampleRatio::Rational convertToOldRational() const;
+
+    private:
+        bool minus = false;
+};
+
+class StringLiteral : public Literal
+{
+    public:
+        explicit StringLiteral(antlr4::tree::TerminalNode * literal);
+        explicit StringLiteral(const String & literal) : Literal(LiteralType::STRING, literal) {}
+
+        template <typename T>
+        T as() const
+        {
+            return asString();
+        }
+};
+
+}

src/Parsers/New/AST/OptimizeQuery.cpp

@@ -0,0 +1,59 @@
+#include <Parsers/New/AST/OptimizeQuery.h>
+
+#include <Interpreters/StorageID.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTOptimizeQuery.h>
+#include <Parsers/New/AST/AlterTableQuery.h>
+#include <Parsers/New/AST/ColumnExpr.h>
+#include <Parsers/New/AST/Identifier.h>
+#include <Parsers/New/AST/Literal.h>
+#include <Parsers/New/ParseTreeVisitor.h>
+
+
+namespace DB::AST
+{
+
+OptimizeQuery::OptimizeQuery(PtrTo<ClusterClause> cluster, PtrTo<TableIdentifier> identifier, PtrTo<PartitionClause> clause, bool final_, bool deduplicate_)
+    : DDLQuery(cluster, {identifier, clause}), final(final_), deduplicate(deduplicate_)
+{
+}
+
+ASTPtr OptimizeQuery::convertToOld() const
+{
+    auto query = std::make_shared<ASTOptimizeQuery>();
+
+    {
+        auto table_id = getTableIdentifier(get(TABLE)->convertToOld());
+        query->database = table_id.database_name;
+        query->table = table_id.table_name;
+        query->uuid = table_id.uuid;
+    }
+
+    if (has(PARTITION))
+    {
+        query->partition = get(PARTITION)->convertToOld();
+        query->children.push_back(query->partition);
+    }
+
+    query->final = final;
+    query->deduplicate = deduplicate;
+    query->cluster = cluster_name;
+
+    return query;
+}
+
+}
+
+namespace DB
+{
+
+using namespace AST;
+
+antlrcpp::Any ParseTreeVisitor::visitOptimizeStmt(ClickHouseParser::OptimizeStmtContext *ctx)
+{
+    auto cluster = ctx->clusterClause() ? visit(ctx->clusterClause()).as<PtrTo<ClusterClause>>() : nullptr;
+    auto clause = ctx->partitionClause() ? visit(ctx->partitionClause()).as<PtrTo<PartitionClause>>() : nullptr;
+    return std::make_shared<OptimizeQuery>(cluster, visit(ctx->tableIdentifier()), clause, !!ctx->FINAL(), !!ctx->DEDUPLICATE());
+}
+
+}