Merge branch 'master' into table-constraints

.gitmodules

@@ -82,3 +82,6 @@
 [submodule "contrib/simdjson"]
 	path = contrib/simdjson
 	url = https://github.com/lemire/simdjson.git
+[submodule "contrib/rapidjson"]
+	path = contrib/rapidjson
+	url = https://github.com/Tencent/rapidjson

CMakeLists.txt

@@ -328,6 +328,7 @@ include (cmake/find_base64.cmake)
 include (cmake/find_hyperscan.cmake)
 include (cmake/find_lfalloc.cmake)
 include (cmake/find_simdjson.cmake)
+include (cmake/find_rapidjson.cmake)
 find_contrib_lib(cityhash)
 find_contrib_lib(farmhash)
 find_contrib_lib(metrohash)

cmake/find_rapidjson.cmake

@@ -0,0 +1,9 @@
+if (NOT EXISTS "${ClickHouse_SOURCE_DIR}/contrib/rapidjson/include/rapidjson/rapidjson.h")
+    message (WARNING "submodule contrib/rapidjson is missing. to fix try run: \n git submodule update --init --recursive")
+    return()
+endif ()
+
+option (USE_RAPIDJSON "Use rapidjson" ON)
+set (RAPIDJSON_INCLUDE_DIR "${ClickHouse_SOURCE_DIR}/contrib/rapidjson/include")
+
+message(STATUS "Using rapidjson=${USE_RAPIDJSON}: ${RAPIDJSON_INCLUDE_DIR}")

contrib/rapidjson

@@ -0,0 +1 @@
+Subproject commit 01950eb7acec78818d68b762efc869bba2420d82

contrib/simdjson

@@ -1 +1 @@
-Subproject commit 681cd3369860f4eada49a387cbff93030f759c95
+Subproject commit 14cd1f7a0b0563db78bda8053a9f6ac2ea95a441

dbms/CMakeLists.txt

@@ -367,6 +367,6 @@ if (ENABLE_TESTS AND USE_GTEST)
     # attach all dbms gtest sources
     grep_gtest_sources(${ClickHouse_SOURCE_DIR}/dbms dbms_gtest_sources)
     add_executable(unit_tests_dbms ${dbms_gtest_sources})
-    target_link_libraries(unit_tests_dbms PRIVATE ${GTEST_BOTH_LIBRARIES} dbms clickhouse_common_zookeeper)
+    target_link_libraries(unit_tests_dbms PRIVATE ${GTEST_BOTH_LIBRARIES} clickhouse_functions clickhouse_parsers dbms clickhouse_common_zookeeper)
     add_check(unit_tests_dbms)
 endif ()

dbms/src/AggregateFunctions/AggregateFunctionQuantile.cpp

@@ -43,8 +43,12 @@ template <typename Value, bool FloatReturn> using FuncQuantilesTDigestWeighted =
 template <template <typename, bool> class Function>
 static constexpr bool supportDecimal()
 {
-    return std::is_same_v<Function<Float32, false>, FuncQuantileExact<Float32, false>> ||
-        std::is_same_v<Function<Float32, false>, FuncQuantilesExact<Float32, false>>;
+    return std::is_same_v<Function<Float32, false>, FuncQuantile<Float32, false>> ||
+        std::is_same_v<Function<Float32, false>, FuncQuantiles<Float32, false>> ||
+        std::is_same_v<Function<Float32, false>, FuncQuantileExact<Float32, false>> ||
+        std::is_same_v<Function<Float32, false>, FuncQuantilesExact<Float32, false>> ||
+        std::is_same_v<Function<Float32, false>, FuncQuantileExactWeighted<Float32, false>> ||
+        std::is_same_v<Function<Float32, false>, FuncQuantilesExactWeighted<Float32, false>>;
 }
 
 
@@ -66,9 +70,9 @@ AggregateFunctionPtr createAggregateFunctionQuantile(const std::string & name, c
 
     if constexpr (supportDecimal<Function>())
     {
-        if (which.idx == TypeIndex::Decimal32) return std::make_shared<Function<Decimal32, true>>(argument_type, params);
-        if (which.idx == TypeIndex::Decimal64) return std::make_shared<Function<Decimal64, true>>(argument_type, params);
-        if (which.idx == TypeIndex::Decimal128) return std::make_shared<Function<Decimal128, true>>(argument_type, params);
+        if (which.idx == TypeIndex::Decimal32) return std::make_shared<Function<Decimal32, false>>(argument_type, params);
+        if (which.idx == TypeIndex::Decimal64) return std::make_shared<Function<Decimal64, false>>(argument_type, params);
+        if (which.idx == TypeIndex::Decimal128) return std::make_shared<Function<Decimal128, false>>(argument_type, params);
     }
 
     throw Exception("Illegal type " + argument_type->getName() + " of argument for aggregate function " + name,

dbms/src/AggregateFunctions/AggregateFunctionWindowFunnel.cpp

@@ -2,6 +2,10 @@
 #include <AggregateFunctions/AggregateFunctionWindowFunnel.h>
 #include <AggregateFunctions/Helpers.h>
 #include <AggregateFunctions/FactoryHelpers.h>
+#include <DataTypes/DataTypeDate.h>
+#include <DataTypes/DataTypeDateTime.h>
+
+#include <ext/range.h>
 
 
 namespace DB
@@ -10,6 +14,7 @@ namespace DB
 namespace
 {
 
+template <template <typename> class Data>
 AggregateFunctionPtr createAggregateFunctionWindowFunnel(const std::string & name, const DataTypes & arguments, const Array & params)
 {
     if (params.size() != 1)
@@ -18,17 +23,36 @@ AggregateFunctionPtr createAggregateFunctionWindowFunnel(const std::string & nam
     if (arguments.size() < 2)
         throw Exception("Aggregate function " + name + " requires one timestamp argument and at least one event condition.", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
 
-    if (arguments.size() > AggregateFunctionWindowFunnelData::max_events + 1)
+    if (arguments.size() > max_events + 1)
         throw Exception("Too many event arguments for aggregate function " + name, ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH);
 
-    return std::make_shared<AggregateFunctionWindowFunnel>(arguments, params);
+    for (const auto i : ext::range(1, arguments.size()))
+    {
+        auto cond_arg = arguments[i].get();
+        if (!isUInt8(cond_arg))
+            throw Exception{"Illegal type " + cond_arg->getName() + " of argument " + toString(i + 1) + " of aggregate function "
+                    + name + ", must be UInt8", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
+    }
+
+    AggregateFunctionPtr res(createWithUnsignedIntegerType<AggregateFunctionWindowFunnel, Data>(*arguments[0], arguments, params));
+    WhichDataType which(arguments.front().get());
+    if (res)
+        return res;
+    else if (which.isDate())
+        return std::make_shared<AggregateFunctionWindowFunnel<DataTypeDate::FieldType, Data<DataTypeDate::FieldType>>>(arguments, params);
+    else if (which.isDateTime())
+        return std::make_shared<AggregateFunctionWindowFunnel<DataTypeDateTime::FieldType, Data<DataTypeDateTime::FieldType>>>(arguments, params);
+
+    throw Exception{"Illegal type " + arguments.front().get()->getName()
+            + " of first argument of aggregate function " + name + ", must be Unsigned Number, Date, DateTime",
+        ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
 }
 
 }
 
 void registerAggregateFunctionWindowFunnel(AggregateFunctionFactory & factory)
 {
-    factory.registerFunction("windowFunnel", createAggregateFunctionWindowFunnel, AggregateFunctionFactory::CaseInsensitive);
+    factory.registerFunction("windowFunnel", createAggregateFunctionWindowFunnel<AggregateFunctionWindowFunnelData>, AggregateFunctionFactory::CaseInsensitive);
 }
 
 }

dbms/src/AggregateFunctions/AggregateFunctionWindowFunnel.h

@@ -9,18 +9,15 @@
 #include <IO/ReadHelpers.h>
 #include <IO/WriteHelpers.h>
 #include <Common/ArenaAllocator.h>
-#include <ext/range.h>
 
 #include <AggregateFunctions/IAggregateFunction.h>
 
-
 namespace DB
 {
 
 namespace ErrorCodes
 {
     extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH;
-    extern const int TOO_MANY_ARGUMENTS_FOR_FUNCTION;
     extern const int ILLEGAL_TYPE_OF_ARGUMENT;
 }
 
@@ -33,10 +30,11 @@ struct ComparePairFirst final
     }
 };
 
+static constexpr auto max_events = 32;
+template <typename T>
 struct AggregateFunctionWindowFunnelData
 {
-    static constexpr auto max_events = 32;
-    using TimestampEvent = std::pair<UInt32, UInt8>;
+    using TimestampEvent = std::pair<T, UInt8>;
 
     static constexpr size_t bytes_on_stack = 64;
     using TimestampEvents = PODArray<TimestampEvent, bytes_on_stack, AllocatorWithStackMemory<Allocator<false>, bytes_on_stack>>;
@@ -51,7 +49,7 @@ struct AggregateFunctionWindowFunnelData
         return events_list.size();
     }
 
-    void add(UInt32 timestamp, UInt8 event)
+    void add(T timestamp, UInt8 event)
     {
         // Since most events should have already been sorted by timestamp.
         if (sorted && events_list.size() > 0 && events_list.back().first > timestamp)
@@ -119,7 +117,7 @@ struct AggregateFunctionWindowFunnelData
         events_list.clear();
         events_list.reserve(size);
 
-        UInt32 timestamp;
+        T timestamp;
         UInt8 event;
 
         for (size_t i = 0; i < size; ++i)
@@ -137,11 +135,12 @@ struct AggregateFunctionWindowFunnelData
   * Usage:
   * - windowFunnel(window)(timestamp, cond1, cond2, cond3, ....)
   */
+template <typename T, typename Data>
 class AggregateFunctionWindowFunnel final
-    : public IAggregateFunctionDataHelper<AggregateFunctionWindowFunnelData, AggregateFunctionWindowFunnel>
+    : public IAggregateFunctionDataHelper<Data, AggregateFunctionWindowFunnel<T, Data>>
 {
 private:
-    UInt32 window;
+    UInt64 window;
     UInt8 events_size;
 
 
@@ -149,22 +148,24 @@ private:
     // The level path must be 1---2---3---...---check_events_size, find the max event level that statisfied the path in the sliding window.
     // If found, returns the max event level, else return 0.
     // The Algorithm complexity is O(n).
-    UInt8 getEventLevel(const AggregateFunctionWindowFunnelData & data) const
+    UInt8 getEventLevel(const Data & data) const
     {
         if (data.size() == 0)
             return 0;
         if (events_size == 1)
             return 1;
 
-        const_cast<AggregateFunctionWindowFunnelData &>(data).sort();
+        const_cast<Data &>(data).sort();
 
-        // events_timestamp stores the timestamp that latest i-th level event happen withing time window after previous level event.
-        // timestamp defaults to -1, which unsigned timestamp value never meet
-        std::vector<Int32> events_timestamp(events_size, -1);
+        /// events_timestamp stores the timestamp that latest i-th level event happen withing time window after previous level event.
+        /// timestamp defaults to -1, which unsigned timestamp value never meet
+        /// there may be some bugs when UInt64 type timstamp overflows Int64, but it works on most cases.
+        std::vector<Int64> events_timestamp(events_size, -1);
         for (const auto & pair : data.events_list)
         {
-            const auto & timestamp = pair.first;
+            const T & timestamp = pair.first;
             const auto & event_idx = pair.second - 1;
+
             if (event_idx == 0)
                 events_timestamp[0] = timestamp;
             else if (events_timestamp[event_idx - 1] >= 0 && timestamp <= events_timestamp[event_idx - 1] + window)
@@ -189,22 +190,8 @@ public:
     }
 
     AggregateFunctionWindowFunnel(const DataTypes & arguments, const Array & params)
-        : IAggregateFunctionDataHelper<AggregateFunctionWindowFunnelData, AggregateFunctionWindowFunnel>(arguments, params)
+        : IAggregateFunctionDataHelper<Data, AggregateFunctionWindowFunnel<T, Data>>(arguments, params)
     {
-        const auto time_arg = arguments.front().get();
-        if (!WhichDataType(time_arg).isDateTime() && !WhichDataType(time_arg).isUInt32())
-            throw Exception{"Illegal type " + time_arg->getName() + " of first argument of aggregate function " + getName()
-                + ", must be DateTime or UInt32", ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
-
-        for (const auto i : ext::range(1, arguments.size()))
-        {
-            auto cond_arg = arguments[i].get();
-            if (!isUInt8(cond_arg))
-                throw Exception{"Illegal type " + cond_arg->getName() + " of argument " + toString(i + 1) + " of aggregate function "
-                        + getName() + ", must be UInt8",
-                    ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
-        }
-
         events_size = arguments.size() - 1;
         window = params.at(0).safeGet<UInt64>();
     }
@@ -217,7 +204,7 @@ public:
 
     void add(AggregateDataPtr place, const IColumn ** columns, const size_t row_num, Arena *) const override
     {
-        const auto timestamp = static_cast<const ColumnVector<UInt32> *>(columns[0])->getData()[row_num];
+        const auto timestamp = static_cast<const ColumnVector<T> *>(columns[0])->getData()[row_num];
         // reverse iteration and stable sorting are needed for events that are qualified by more than one condition.
         for (auto i = events_size; i > 0; --i)
         {

dbms/src/AggregateFunctions/QuantileExactWeighted.h

@@ -20,12 +20,22 @@ namespace ErrorCodes
 template <typename Value>
 struct QuantileExactWeighted
 {
+    struct Int128Hash
+    {
+        size_t operator()(Int128 x) const
+        {
+            return CityHash_v1_0_2::Hash128to64({x >> 64, x & 0xffffffffffffffffll});
+        }
+    };
+
     using Weight = UInt64;
+    using UnderlyingType = typename NativeType<Value>::Type;
+    using Hasher = std::conditional_t<std::is_same_v<Value, Decimal128>, Int128Hash, HashCRC32<UnderlyingType>>;
 
     /// When creating, the hash table must be small.
     using Map = HashMap<
-        Value, Weight,
-        HashCRC32<Value>,
+        UnderlyingType, Weight,
+        Hasher,
         HashTableGrower<4>,
         HashTableAllocatorWithStackMemory<sizeof(std::pair<Value, Weight>) * (1 << 3)>
     >;
@@ -39,7 +49,7 @@ struct QuantileExactWeighted
             ++map[x];
     }
 
-    void add(const Value & x, const Weight & weight)
+    void add(const Value & x, Weight weight)
     {
         if (!isNaN(x))
             map[x] += weight;

dbms/src/Client/Connection.h

@@ -12,8 +12,7 @@
 #include <Core/Protocol.h>
 #include <Core/QueryProcessingStage.h>
 
-#include <DataStreams/IBlockInputStream.h>
-#include <DataStreams/IBlockOutputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <DataStreams/BlockStreamProfileInfo.h>
 
 #include <IO/ConnectionTimeouts.h>

dbms/src/Common/ZooKeeper/ZooKeeperImpl.cpp

@@ -1430,6 +1430,8 @@ void ZooKeeper::pushRequest(RequestInfo && info)
         if (!info.request->xid)
         {
             info.request->xid = next_xid.fetch_add(1);
+            if (info.request->xid == close_xid)
+                throw Exception("xid equal to close_xid", ZSESSIONEXPIRED);
             if (info.request->xid < 0)
                 throw Exception("XID overflow", ZSESSIONEXPIRED);
         }

dbms/src/Common/config.h.in

@@ -26,6 +26,7 @@
 #cmakedefine01 USE_SSL
 #cmakedefine01 USE_HYPERSCAN
 #cmakedefine01 USE_SIMDJSON
+#cmakedefine01 USE_RAPIDJSON
 #cmakedefine01 USE_LFALLOC
 #cmakedefine01 USE_LFALLOC_RANDOM_HINT
 

dbms/src/Core/AccurateComparison.h

@@ -430,6 +430,13 @@ inline bool_if_safe_conversion<A, B> greaterOrEqualsOp(A a, B b)
 template <typename From, typename To>
 inline bool NO_SANITIZE_UNDEFINED convertNumeric(From value, To & result)
 {
+    /// If the type is actually the same it's not necessary to do any checks.
+    if constexpr (std::is_same_v<From, To>)
+    {
+        result = value;
+        return true;
+    }
+
     /// Note that NaNs doesn't compare equal to anything, but they are still in range of any Float type.
     if (isNaN(value) && std::is_floating_point_v<To>)
     {

dbms/src/Core/Settings.h

@@ -323,8 +323,9 @@ struct Settings : public SettingsCollection<Settings>
     M(SettingBool, allow_experimental_data_skipping_indices, false, "If it is set to true, data skipping indices can be used in CREATE TABLE/ALTER TABLE queries.") \
     \
     M(SettingBool, allow_hyperscan, true, "Allow functions that use Hyperscan library. Disable to avoid potentially long compilation times and excessive resource usage.") \
+    M(SettingBool, allow_simdjson, 1, "Allow using simdjson library in 'JSON*' functions if AVX2 instructions are available. If disabled rapidjson will be used.") \
     \
-    M(SettingUInt64, max_partitions_per_insert_block, 100, "Limit maximum number of partitions in single INSERTed block. Zero means unlimited. Throw exception if the block contains too many partitions. This setting is a safety threshold, because using large number of partitions is a common misconception.") \
+    M(SettingUInt64, max_partitions_per_insert_block, 100, "Limit maximum number of partitions in single INSERTed block. Zero means unlimited. Throw exception if the block contains too many partitions. This setting is a safety threshold, because using large number of partitions is a common misconception.")
 
     DECLARE_SETTINGS_COLLECTION(LIST_OF_SETTINGS)
 

dbms/src/Core/Types.h

@@ -165,6 +165,11 @@ template <> constexpr bool IsDecimalNumber<Decimal32> = true;
 template <> constexpr bool IsDecimalNumber<Decimal64> = true;
 template <> constexpr bool IsDecimalNumber<Decimal128> = true;
 
+template <typename T> struct NativeType { using Type = T; };
+template <> struct NativeType<Decimal32> { using Type = Int32; };
+template <> struct NativeType<Decimal64> { using Type = Int64; };
+template <> struct NativeType<Decimal128> { using Type = Int128; };
+
 }
 
 /// Specialization of `std::hash` for the Decimal<T> types.

dbms/src/DataStreams/BlockIO.h

@@ -1,7 +1,8 @@
 #pragma once
 
-#include <DataStreams/IBlockInputStream.h>
-#include <DataStreams/IBlockOutputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
+
+#include <functional>
 
 
 namespace DB

dbms/src/DataStreams/BlockStreamProfileInfo.h

@@ -1,8 +1,10 @@
 #pragma once
 
-#include <vector>
-#include <Common/Stopwatch.h>
 #include <Core/Types.h>
+#include <DataStreams/IBlockStream_fwd.h>
+#include <Common/Stopwatch.h>
+
+#include <vector>
 
 namespace DB
 {
@@ -10,7 +12,6 @@ namespace DB
 class Block;
 class ReadBuffer;
 class WriteBuffer;
-class IBlockInputStream;
 
 /// Information for profiling. See IBlockInputStream.h
 struct BlockStreamProfileInfo

dbms/src/DataStreams/ExpressionBlockInputStream.cpp

@@ -9,6 +9,8 @@ ExpressionBlockInputStream::ExpressionBlockInputStream(const BlockInputStreamPtr
     : expression(expression_)
 {
     children.push_back(input);
+    cached_header = children.back()->getHeader();
+    expression->execute(cached_header, true);
 }
 
 String ExpressionBlockInputStream::getName() const { return "Expression"; }
@@ -23,9 +25,7 @@ Block ExpressionBlockInputStream::getTotals()
 
 Block ExpressionBlockInputStream::getHeader() const
 {
-    Block res = children.back()->getHeader();
-    expression->execute(res, true);
-    return res;
+    return cached_header.cloneEmpty();
 }
 
 Block ExpressionBlockInputStream::readImpl()

dbms/src/DataStreams/ExpressionBlockInputStream.h

@@ -30,6 +30,7 @@ protected:
 
 private:
     ExpressionActionsPtr expression;
+    Block cached_header;
 };
 
 }

dbms/src/DataStreams/IBlockInputStream.h

@@ -2,6 +2,7 @@
 
 #include <Core/Block.h>
 #include <Core/SortDescription.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <DataStreams/BlockStreamProfileInfo.h>
 #include <DataStreams/SizeLimits.h>
 #include <IO/Progress.h>
@@ -21,14 +22,10 @@ namespace ErrorCodes
     extern const int QUERY_WAS_CANCELLED;
 }
 
-class IBlockInputStream;
 class ProcessListElement;
 class QuotaForIntervals;
 class QueryStatus;
 
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-using BlockInputStreams = std::vector<BlockInputStreamPtr>;
-
 /** Callback to track the progress of the query.
   * Used in IBlockInputStream and Context.
   * The function takes the number of rows in the last block, the number of bytes in the last block.

dbms/src/DataStreams/IBlockOutputStream.h

@@ -1,11 +1,14 @@
 #pragma once
 
+#include <Core/Block.h>
+#include <DataStreams/IBlockStream_fwd.h>
+#include <Storages/TableStructureLockHolder.h>
+
+#include <boost/noncopyable.hpp>
+
+#include <memory>
 #include <string>
 #include <vector>
-#include <memory>
-#include <boost/noncopyable.hpp>
-#include <Core/Block.h>
-#include <Storages/TableStructureLockHolder.h>
 
 
 namespace DB
@@ -64,6 +67,4 @@ private:
     std::vector<TableStructureReadLockHolder> table_locks;
 };
 
-using BlockOutputStreamPtr = std::shared_ptr<IBlockOutputStream>;
-
 }

dbms/src/DataStreams/IBlockStream_fwd.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <memory>
+#include <vector>
+
+namespace DB
+{
+
+class IBlockInputStream;
+class IBlockOutputStream;
+
+using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
+using BlockInputStreams = std::vector<BlockInputStreamPtr>;
+using BlockOutputStreamPtr = std::shared_ptr<IBlockOutputStream>;
+
+}

dbms/src/DataStreams/ParallelInputsProcessor.h

@@ -8,7 +8,7 @@
 
 #include <common/logger_useful.h>
 
-#include <DataStreams/IBlockInputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <Common/setThreadName.h>
 #include <Common/CurrentMetrics.h>
 #include <Common/CurrentThread.h>

dbms/src/DataStreams/copyData.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <DataStreams/IBlockStream_fwd.h>
+
 #include <atomic>
 #include <functional>
 
@@ -7,8 +9,6 @@
 namespace DB
 {
 
-class IBlockInputStream;
-class IBlockOutputStream;
 class Block;
 
 /** Copies data from the InputStream into the OutputStream

dbms/src/Databases/DatabaseDictionary.h

@@ -4,7 +4,7 @@
 #include <unordered_set>
 #include <Databases/DatabasesCommon.h>
 #include <Databases/IDatabase.h>
-#include <Storages/IStorage.h>
+#include <Storages/IStorage_fwd.h>
 
 
 namespace Poco

dbms/src/Databases/DatabaseOrdinary.cpp

@@ -1,27 +1,28 @@
 #include <iomanip>
 
-#include <Poco/Event.h>
-#include <Poco/DirectoryIterator.h>
-#include <common/logger_useful.h>
-
-#include <Databases/DatabaseOrdinary.h>
-#include <Databases/DatabaseMemory.h>
-#include <Databases/DatabasesCommon.h>
-#include <Common/typeid_cast.h>
-#include <Common/escapeForFileName.h>
-#include <Common/StringUtils/StringUtils.h>
-#include <Common/Stopwatch.h>
-#include <Common/ThreadPool.h>
-#include <Parsers/ASTCreateQuery.h>
-#include <Parsers/parseQuery.h>
-#include <Parsers/ParserCreateQuery.h>
-#include <Interpreters/Context.h>
 #include <Core/Settings.h>
-#include <Interpreters/InterpreterCreateQuery.h>
-#include <IO/WriteBufferFromFile.h>
+#include <Databases/DatabaseMemory.h>
+#include <Databases/DatabaseOrdinary.h>
+#include <Databases/DatabasesCommon.h>
 #include <IO/ReadBufferFromFile.h>
-#include <IO/WriteHelpers.h>
 #include <IO/ReadHelpers.h>
+#include <IO/WriteBufferFromFile.h>
+#include <IO/WriteHelpers.h>
+#include <Interpreters/Context.h>
+#include <Interpreters/InterpreterCreateQuery.h>
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ParserCreateQuery.h>
+#include <Parsers/parseQuery.h>
+#include <Storages/IStorage.h>
+
+#include <Poco/DirectoryIterator.h>
+#include <Poco/Event.h>
+#include <Common/Stopwatch.h>
+#include <Common/StringUtils/StringUtils.h>
+#include <Common/ThreadPool.h>
+#include <Common/escapeForFileName.h>
+#include <Common/typeid_cast.h>
+#include <common/logger_useful.h>
 #include <ext/scope_guard.h>
 
 

dbms/src/Databases/DatabasesCommon.cpp

@@ -1,14 +1,16 @@
-#include <sstream>
+#include <Databases/DatabasesCommon.h>
 
-#include <Common/typeid_cast.h>
-#include <Parsers/parseQuery.h>
-#include <Parsers/ParserCreateQuery.h>
-#include <Parsers/ASTCreateQuery.h>
-#include <Parsers/formatAST.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/InterpreterCreateQuery.h>
+#include <Parsers/ASTCreateQuery.h>
+#include <Parsers/ParserCreateQuery.h>
+#include <Parsers/formatAST.h>
+#include <Parsers/parseQuery.h>
+#include <Storages/IStorage.h>
 #include <Storages/StorageFactory.h>
-#include <Databases/DatabasesCommon.h>
+#include <Common/typeid_cast.h>
+
+#include <sstream>
 
 
 namespace DB

dbms/src/Databases/DatabasesCommon.h

@@ -2,7 +2,7 @@
 
 #include <Core/Types.h>
 #include <Parsers/IAST.h>
-#include <Storages/IStorage.h>
+#include <Storages/IStorage_fwd.h>
 #include <Databases/IDatabase.h>
 
 

dbms/src/Databases/IDatabase.h

@@ -6,6 +6,7 @@
 #include <Parsers/IAST_fwd.h>
 #include <Storages/ColumnsDescription.h>
 #include <Storages/IndicesDescription.h>
+#include <Storages/IStorage_fwd.h>
 #include <Poco/File.h>
 #include <Common/ThreadPool.h>
 #include <Common/escapeForFileName.h>
@@ -20,9 +21,6 @@ namespace DB
 
 class Context;
 
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
-
 struct Settings;
 
 

dbms/src/Dictionaries/CacheDictionary.inc.h

@@ -3,6 +3,7 @@
 #include <Columns/ColumnsNumber.h>
 #include <Common/ProfilingScopedRWLock.h>
 #include <Common/typeid_cast.h>
+#include <DataStreams/IBlockInputStream.h>
 #include <ext/map.h>
 #include <ext/range.h>
 #include <ext/size.h>

dbms/src/Dictionaries/ComplexKeyCacheDictionary.h

@@ -20,6 +20,7 @@
 #include "DictionaryStructure.h"
 #include "IDictionary.h"
 #include "IDictionarySource.h"
+#include <DataStreams/IBlockInputStream.h>
 
 
 namespace ProfileEvents

dbms/src/Dictionaries/ComplexKeyHashedDictionary.h

@@ -7,6 +7,7 @@
 #include <Columns/ColumnString.h>
 #include <Common/Arena.h>
 #include <Common/HashTable/HashMap.h>
+#include <Core/Block.h>
 #include <common/StringRef.h>
 #include <ext/range.h>
 #include "DictionaryStructure.h"

dbms/src/Dictionaries/DictionarySourceFactory.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "IDictionarySource.h"
+#include <Core/Block.h>
 
 #include <unordered_map>
 #include <ext/singleton.h>

dbms/src/Dictionaries/ExecutableDictionarySource.h

@@ -2,12 +2,10 @@
 
 #include "DictionaryStructure.h"
 #include "IDictionarySource.h"
+#include <Core/Block.h>
 
 
-namespace Poco
-{
-class Logger;
-}
+namespace Poco { class Logger; }
 
 
 namespace DB

dbms/src/Dictionaries/FileDictionarySource.h

@@ -2,6 +2,7 @@
 
 #include <Poco/Timestamp.h>
 #include "IDictionarySource.h"
+#include <Core/Block.h>
 
 
 namespace DB

dbms/src/Dictionaries/FlatDictionary.h

@@ -6,6 +6,7 @@
 #include <Columns/ColumnDecimal.h>
 #include <Columns/ColumnString.h>
 #include <Common/Arena.h>
+#include <Core/Block.h>
 #include <ext/range.h>
 #include <ext/size.h>
 #include "DictionaryStructure.h"

dbms/src/Dictionaries/HashedDictionary.h

@@ -5,6 +5,7 @@
 #include <variant>
 #include <Columns/ColumnDecimal.h>
 #include <Columns/ColumnString.h>
+#include <Core/Block.h>
 #include <Common/HashTable/HashMap.h>
 #include <ext/range.h>
 #include "DictionaryStructure.h"

dbms/src/Dictionaries/IDictionary.h

@@ -1,27 +1,27 @@
 #pragma once
 
-#include <chrono>
-#include <memory>
+
 #include <Core/Field.h>
 #include <Core/Names.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <Interpreters/IExternalLoadable.h>
 #include <Poco/Util/XMLConfiguration.h>
 #include <Common/PODArray.h>
 #include <common/StringRef.h>
 #include "IDictionarySource.h"
 
+#include <chrono>
+#include <memory>
+
 namespace DB
 {
+
 struct IDictionaryBase;
 using DictionaryPtr = std::unique_ptr<IDictionaryBase>;
 
 struct DictionaryStructure;
 class ColumnString;
 
-class IBlockInputStream;
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-
-
 struct IDictionaryBase : public IExternalLoadable
 {
     using Key = UInt64;

dbms/src/Dictionaries/IDictionarySource.h

@@ -1,7 +1,9 @@
 #pragma once
 
+#include <Columns/IColumn.h>
+#include <DataStreams/IBlockStream_fwd.h>
+
 #include <vector>
-#include <DataStreams/IBlockInputStream.h>
 
 
 namespace DB

dbms/src/Dictionaries/MongoDBDictionarySource.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <Common/config.h>
+#include <Core/Block.h>
 #if USE_POCO_MONGODB
 
 #    include "DictionaryStructure.h"

dbms/src/Dictionaries/MySQLDictionarySource.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <Common/config.h>
+#include <Core/Block.h>
 #if USE_MYSQL
 
 #    include <common/LocalDateTime.h>

dbms/src/Dictionaries/readInvalidateQuery.h

@@ -1,11 +1,12 @@
 #pragma once
+
+#include <DataStreams/IBlockStream_fwd.h>
+
 #include <string>
 
 namespace DB
 {
 
-class IBlockInputStream;
-
 /// Using in MySQLDictionarySource and XDBCDictionarySource after processing invalidate_query.
 std::string readInvalidateQuery(IBlockInputStream & block_input_stream);
 

dbms/src/Formats/FormatFactory.h

@@ -1,10 +1,12 @@
 #pragma once
 
-#include <memory>
-#include <functional>
-#include <unordered_map>
-#include <ext/singleton.h>
 #include <Core/Types.h>
+#include <DataStreams/IBlockStream_fwd.h>
+#include <ext/singleton.h>
+
+#include <functional>
+#include <memory>
+#include <unordered_map>
 
 
 namespace DB
@@ -17,13 +19,6 @@ struct FormatSettings;
 class ReadBuffer;
 class WriteBuffer;
 
-class IBlockInputStream;
-class IBlockOutputStream;
-
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-using BlockOutputStreamPtr = std::shared_ptr<IBlockOutputStream>;
-
-
 /** Allows to create an IBlockInputStream or IBlockOutputStream by the name of the format.
   * Note: format and compression are independent things.
   */

dbms/src/Functions/CMakeLists.txt

@@ -73,3 +73,7 @@ endif()
 if(USE_SIMDJSON)
     target_link_libraries(clickhouse_functions PRIVATE ${SIMDJSON_LIBRARY})
 endif()
+
+if(USE_RAPIDJSON)
+    target_include_directories(clickhouse_functions SYSTEM PRIVATE ${RAPIDJSON_INCLUDE_DIR})
+endif()

dbms/src/Functions/DummyJSONParser.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include <common/StringRef.h>
+#include <Common/Exception.h>
+#include <Core/Types.h>
+
+namespace DB
+{
+namespace ErrorCodes
+{
+    extern const int NOT_IMPLEMENTED;
+}
+
+/// This class can be used as an argument for the template class FunctionJSON when we unable to parse JSONs.
+/// It can't do anything useful and just throws an exception.
+struct DummyJSONParser
+{
+    static constexpr bool need_preallocate = false;
+    void preallocate(size_t) {}
+
+    bool parse(const StringRef &) { throw Exception{"Functions JSON* are not supported without AVX2", ErrorCodes::NOT_IMPLEMENTED}; }
+
+    using Iterator = std::nullptr_t;
+    Iterator getRoot() const { return nullptr; }
+
+    static bool isInt64(const Iterator &) { return false; }
+    static bool isUInt64(const Iterator &) { return false; }
+    static bool isDouble(const Iterator &) { return false; }
+    static bool isString(const Iterator &) { return false; }
+    static bool isArray(const Iterator &) { return false; }
+    static bool isObject(const Iterator &) { return false; }
+    static bool isBool(const Iterator &) { return false; }
+    static bool isNull(const Iterator &) { return true; }
+
+    static Int64 getInt64(const Iterator &) { return 0; }
+    static UInt64 getUInt64(const Iterator &) { return 0; }
+    static double getDouble(const Iterator &) { return 0; }
+    static bool getBool(const Iterator &) { return false; }
+    static StringRef getString(const Iterator &) { return {}; }
+
+    static size_t sizeOfArray(const Iterator &) { return 0; }
+    static bool firstArrayElement(Iterator &) { return false; }
+    static bool arrayElementByIndex(Iterator &, size_t) { return false; }
+    static bool nextArrayElement(Iterator &) { return false; }
+
+    static size_t sizeOfObject(const Iterator &) { return 0; }
+    static bool firstObjectMember(Iterator &) { return false; }
+    static bool firstObjectMember(Iterator &, StringRef &) { return false; }
+    static bool objectMemberByIndex(Iterator &, size_t) { return false; }
+    static bool objectMemberByName(Iterator &, const StringRef &) { return false; }
+    static bool nextObjectMember(Iterator &) { return false; }
+    static bool nextObjectMember(Iterator &, StringRef &) { return false; }
+    static bool isObjectMember(const Iterator &) { return false; }
+    static StringRef getKey(const Iterator &) { return {}; }
+};
+
+}

dbms/src/Functions/FunctionBinaryArithmetic.h

@@ -98,11 +98,6 @@ template <typename, typename> struct GreatestBaseImpl;
 template <typename, typename> struct ModuloImpl;
 
 
-template <typename T> struct NativeType { using Type = T; };
-template <> struct NativeType<Decimal32> { using Type = Int32; };
-template <> struct NativeType<Decimal64> { using Type = Int64; };
-template <> struct NativeType<Decimal128> { using Type = Int128; };
-
 /// Binary operations for Decimals need scale args
 /// +|- scale one of args (which scale factor is not 1). ScaleR = oneof(Scale1, Scale2);
 /// *   no agrs scale. ScaleR = Scale1 + Scale2;

dbms/src/Functions/FunctionJoinGet.h

@@ -1,11 +1,10 @@
 #include <Functions/IFunction.h>
+#include <Storages/IStorage_fwd.h>
 #include <Storages/TableStructureLockHolder.h>
 
 namespace DB
 {
 class Context;
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
 class Join;
 using JoinPtr = std::shared_ptr<Join>;
 

dbms/src/Functions/FunctionsJSON.cpp

@@ -1,378 +1,24 @@
 #include <Functions/FunctionsJSON.h>
 #include <Functions/FunctionFactory.h>
-#include <Common/config.h>
 
-#if USE_SIMDJSON
-#include <DataTypes/DataTypeArray.h>
-#include <DataTypes/DataTypeNullable.h>
-#include <DataTypes/DataTypeString.h>
-#include <DataTypes/DataTypeTuple.h>
-#include <DataTypes/DataTypesNumber.h>
-
-
-namespace DB
-{
-template <typename T>
-class JSONNullableImplBase
-{
-public:
-    static DataTypePtr getType() { return std::make_shared<DataTypeNullable>(std::make_shared<T>()); }
-
-    static Field getDefault() { return {}; }
-};
-
-class JSONHasImpl : public JSONNullableImplBase<DataTypeUInt8>
-{
-public:
-    static constexpr auto name{"jsonHas"};
-
-    static Field getValue(ParsedJson::iterator &) { return {1}; }
-};
-
-class JSONLengthImpl : public JSONNullableImplBase<DataTypeUInt64>
-{
-public:
-    static constexpr auto name{"jsonLength"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (!pjh.is_object_or_array())
-            return getDefault();
-
-        size_t size = 0;
-
-        if (pjh.down())
-        {
-            size += 1;
-
-            while (pjh.next())
-                size += 1;
-        }
-
-        return {size};
-    }
-};
-
-class JSONTypeImpl : public JSONNullableImplBase<DataTypeString>
-{
-public:
-    static constexpr auto name{"jsonType"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        switch (pjh.get_type())
-        {
-            case '[':
-                return "Array";
-            case '{':
-                return "Object";
-            case '"':
-                return "String";
-            case 'l':
-                return "Int64";
-            case 'd':
-                return "Float64";
-            case 't':
-                return "Bool";
-            case 'f':
-                return "Bool";
-            case 'n':
-                return "Null";
-            default:
-                return "Unknown";
-        }
-    }
-};
-
-class JSONExtractImpl
-{
-public:
-    static constexpr auto name{"jsonExtract"};
-
-    static DataTypePtr getType(const DataTypePtr & type)
-    {
-        WhichDataType which{type};
-
-        if (which.isNativeUInt() || which.isNativeInt() || which.isFloat() || which.isEnum() || which.isDateOrDateTime()
-            || which.isStringOrFixedString() || which.isInterval())
-            return std::make_shared<DataTypeNullable>(type);
-
-        if (which.isArray())
-        {
-            auto array_type = static_cast<const DataTypeArray *>(type.get());
-
-            return std::make_shared<DataTypeArray>(getType(array_type->getNestedType()));
-        }
-
-        if (which.isTuple())
-        {
-            auto tuple_type = static_cast<const DataTypeTuple *>(type.get());
-
-            DataTypes types;
-            types.reserve(tuple_type->getElements().size());
-
-            for (const DataTypePtr & element : tuple_type->getElements())
-            {
-                types.push_back(getType(element));
-            }
-
-            return std::make_shared<DataTypeTuple>(std::move(types));
-        }
-
-        throw Exception{"Unsupported return type schema: " + type->getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
-    }
-
-    static Field getDefault(const DataTypePtr & type)
-    {
-        WhichDataType which{type};
-
-        if (which.isNativeUInt() || which.isNativeInt() || which.isFloat() || which.isEnum() || which.isDateOrDateTime()
-            || which.isStringOrFixedString() || which.isInterval())
-            return {};
-
-        if (which.isArray())
-            return {Array{}};
-
-        if (which.isTuple())
-        {
-            auto tuple_type = static_cast<const DataTypeTuple *>(type.get());
-
-            Tuple tuple;
-            tuple.toUnderType().reserve(tuple_type->getElements().size());
-
-            for (const DataTypePtr & element : tuple_type->getElements())
-                tuple.toUnderType().push_back(getDefault(element));
-
-            return {tuple};
-        }
-
-        // should not reach
-        throw Exception{"Unsupported return type schema: " + type->getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
-    }
-
-    static Field getValue(ParsedJson::iterator & pjh, const DataTypePtr & type)
-    {
-        WhichDataType which{type};
-
-        if (which.isNativeUInt() || which.isNativeInt() || which.isEnum() || which.isDateOrDateTime() || which.isInterval())
-        {
-            if (pjh.is_integer())
-                return {pjh.get_integer()};
-            else
-                return getDefault(type);
-        }
-
-        if (which.isFloat())
-        {
-            if (pjh.is_integer())
-                return {static_cast<double>(pjh.get_integer())};
-            else if (pjh.is_double())
-                return {pjh.get_double()};
-            else
-                return getDefault(type);
-        }
-
-        if (which.isStringOrFixedString())
-        {
-            if (pjh.is_string())
-                return {String{pjh.get_string()}};
-            else
-                return getDefault(type);
-        }
-
-        if (which.isArray())
-        {
-            if (!pjh.is_object_or_array())
-                return getDefault(type);
-
-            auto array_type = static_cast<const DataTypeArray *>(type.get());
-
-            Array array;
-
-            bool first = true;
-
-            while (first ? pjh.down() : pjh.next())
-            {
-                first = false;
-
-                ParsedJson::iterator pjh1{pjh};
-
-                array.push_back(getValue(pjh1, array_type->getNestedType()));
-            }
-
-            return {array};
-        }
-
-        if (which.isTuple())
-        {
-            if (!pjh.is_object_or_array())
-                return getDefault(type);
-
-            auto tuple_type = static_cast<const DataTypeTuple *>(type.get());
-
-            Tuple tuple;
-            tuple.toUnderType().reserve(tuple_type->getElements().size());
-
-            bool valid = true;
-            bool first = true;
-
-            for (const DataTypePtr & element : tuple_type->getElements())
-            {
-                if (valid)
-                {
-                    valid &= first ? pjh.down() : pjh.next();
-                    first = false;
-
-                    ParsedJson::iterator pjh1{pjh};
-
-                    tuple.toUnderType().push_back(getValue(pjh1, element));
-                }
-                else
-                    tuple.toUnderType().push_back(getDefault(element));
-            }
-
-            return {tuple};
-        }
-
-        // should not reach
-        throw Exception{"Unsupported return type schema: " + type->getName(), ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT};
-    }
-};
-
-class JSONExtractUIntImpl : public JSONNullableImplBase<DataTypeUInt64>
-{
-public:
-    static constexpr auto name{"jsonExtractUInt"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (pjh.is_integer())
-            return {pjh.get_integer()};
-        else
-            return getDefault();
-    }
-};
-
-class JSONExtractIntImpl : public JSONNullableImplBase<DataTypeInt64>
-{
-public:
-    static constexpr auto name{"jsonExtractInt"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (pjh.is_integer())
-            return {pjh.get_integer()};
-        else
-            return getDefault();
-    }
-};
-
-class JSONExtractFloatImpl : public JSONNullableImplBase<DataTypeFloat64>
-{
-public:
-    static constexpr auto name{"jsonExtractFloat"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (pjh.is_double())
-            return {pjh.get_double()};
-        else
-            return getDefault();
-    }
-};
-
-class JSONExtractBoolImpl : public JSONNullableImplBase<DataTypeUInt8>
-{
-public:
-    static constexpr auto name{"jsonExtractBool"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (pjh.get_type() == 't')
-            return {1};
-        else if (pjh.get_type() == 'f')
-            return {0};
-        else
-            return getDefault();
-    }
-};
-
-// class JSONExtractRawImpl: public JSONNullableImplBase<DataTypeString>
-// {
-// public:
-//     static constexpr auto name {"jsonExtractRaw"};
-
-//     static Field getValue(ParsedJson::iterator & pjh)
-//     {
-//         //
-//     }
-// };
-
-class JSONExtractStringImpl : public JSONNullableImplBase<DataTypeString>
-{
-public:
-    static constexpr auto name{"jsonExtractString"};
-
-    static Field getValue(ParsedJson::iterator & pjh)
-    {
-        if (pjh.is_string())
-            return {String{pjh.get_string()}};
-        else
-            return getDefault();
-    }
-};
-
-}
-#else
-namespace DB
-{
-struct JSONHasImpl { static constexpr auto name{"jsonHas"}; };
-struct JSONLengthImpl { static constexpr auto name{"jsonLength"}; };
-struct JSONTypeImpl { static constexpr auto name{"jsonType"}; };
-struct JSONExtractImpl { static constexpr auto name{"jsonExtract"}; };
-struct JSONExtractUIntImpl { static constexpr auto name{"jsonExtractUInt"}; };
-struct JSONExtractIntImpl { static constexpr auto name{"jsonExtractInt"}; };
-struct JSONExtractFloatImpl { static constexpr auto name{"jsonExtractFloat"}; };
-struct JSONExtractBoolImpl { static constexpr auto name{"jsonExtractBool"}; };
-//struct JSONExtractRawImpl { static constexpr auto name {"jsonExtractRaw"}; };
-struct JSONExtractStringImpl { static constexpr auto name{"jsonExtractString"}; };
-}
-#endif
 
 namespace DB
 {
 
 void registerFunctionsJSON(FunctionFactory & factory)
 {
-#if USE_SIMDJSON
-    if (__builtin_cpu_supports("avx2"))
-    {
-        factory.registerFunction<FunctionJSONBase<JSONHasImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONLengthImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONTypeImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractImpl, true>>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractUIntImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractIntImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractFloatImpl, false>>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractBoolImpl, false>>();
-        // factory.registerFunction<FunctionJSONBase<
-        //     JSONExtractRawImpl,
-        //     false
-        // >>();
-        factory.registerFunction<FunctionJSONBase<JSONExtractStringImpl, false>>();
-        return;
-    }
-#endif
-    factory.registerFunction<FunctionJSONDummy<JSONHasImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONLengthImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONTypeImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractUIntImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractIntImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractFloatImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractBoolImpl>>();
-    //factory.registerFunction<FunctionJSONDummy<JSONExtractRawImpl>>();
-    factory.registerFunction<FunctionJSONDummy<JSONExtractStringImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONHas, JSONHasImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONLength, JSONLengthImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONKey, JSONKeyImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONType, JSONTypeImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractInt, JSONExtractInt64Impl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractUInt, JSONExtractUInt64Impl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractFloat, JSONExtractFloat64Impl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractBool, JSONExtractBoolImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractString, JSONExtractStringImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtract, JSONExtractImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractKeysAndValues, JSONExtractKeysAndValuesImpl>>();
+    factory.registerFunction<FunctionJSON<NameJSONExtractRaw, JSONExtractRawImpl>>();
 }
 
 }

dbms/src/Functions/RapidJSONParser.h

@@ -0,0 +1,211 @@
+#pragma once
+
+#include <Common/config.h>
+#if USE_RAPIDJSON
+
+#include <common/StringRef.h>
+#include <Common/Exception.h>
+#include <Core/Types.h>
+
+#include <rapidjson/document.h>
+
+
+namespace DB
+{
+
+/// This class can be used as an argument for the template class FunctionJSON.
+/// It provides ability to parse JSONs using rapidjson library.
+struct RapidJSONParser
+{
+    static constexpr bool need_preallocate = false;
+    void preallocate(size_t) {}
+
+    bool parse(const StringRef & json)
+    {
+        document.Parse(json.data);
+        return !document.HasParseError();
+    }
+
+    struct Iterator
+    {
+    public:
+        Iterator() {}
+        Iterator(const rapidjson::Document & document) : value(&document) {}
+        Iterator(const Iterator & src)
+            : value(src.value)
+            , is_object_member(src.is_object_member)
+            , current_in_array(src.current_in_array)
+            , end_of_array(src.end_of_array) {}
+
+        Iterator & operator =(const Iterator & src)
+        {
+            value = src.value;
+            is_object_member = src.is_object_member;
+            current_in_array = src.current_in_array;
+            end_of_array = src.end_of_array;
+            return *this;
+        }
+
+        bool isInt64() const { return value->IsInt64(); }
+        bool isUInt64() const { return value->IsUint64(); }
+        bool isDouble() const { return value->IsDouble(); }
+        bool isBool() const { return value->IsBool(); }
+        bool isString() const { return value->IsString(); }
+        bool isArray() const { return value->IsArray(); }
+        bool isObject() const { return value->IsObject(); }
+        bool isNull() const { return value->IsNull(); }
+
+        Int64 getInt64() const { return value->GetInt64(); }
+        UInt64 getUInt64() const { return value->GetUint64(); }
+        double getDouble() const { return value->GetDouble(); }
+        bool getBool() const { return value->GetBool(); }
+        StringRef getString() const { return {value->GetString(), value->GetStringLength()}; }
+
+        size_t sizeOfArray() const { return value->Size(); }
+
+        bool arrayElementByIndex(size_t index)
+        {
+            if (index >= value->Size())
+                return false;
+            setRange(value->Begin() + index, value->End());
+            value = current_in_array++;
+            return true;
+        }
+
+        bool nextArrayElement()
+        {
+            if (current_in_array == end_of_array)
+                return false;
+            value = current_in_array++;
+            return true;
+        }
+
+        size_t sizeOfObject() const { return value->MemberCount(); }
+
+        bool objectMemberByIndex(size_t index)
+        {
+            if (index >= value->MemberCount())
+                return false;
+            setRange(value->MemberBegin() + index, value->MemberEnd());
+            value = &(current_in_object++)->value;
+            return true;
+        }
+
+        bool objectMemberByIndex(size_t index, StringRef & key)
+        {
+            if (index >= value->MemberCount())
+                return false;
+            setRange(value->MemberBegin() + index, value->MemberEnd());
+            key = getKeyImpl(current_in_object);
+            value = &(current_in_object++)->value;
+            return true;
+        }
+
+        bool objectMemberByName(const StringRef & name)
+        {
+            auto it = value->FindMember(name.data);
+            if (it == value->MemberEnd())
+                return false;
+            setRange(it, value->MemberEnd());
+            value = &(current_in_object++)->value;
+            return true;
+        }
+
+        bool nextObjectMember()
+        {
+            if (current_in_object == end_of_object)
+                return false;
+            value = &(current_in_object++)->value;
+            return true;
+        }
+
+        bool nextObjectMember(StringRef & key)
+        {
+            if (current_in_object == end_of_object)
+                return false;
+            key = getKeyImpl(current_in_object);
+            value = &(current_in_object++)->value;
+            return true;
+        }
+
+        bool isObjectMember() const { return is_object_member; }
+
+        StringRef getKey() const
+        {
+            return getKeyImpl(current_in_object - 1);
+        }
+
+    private:
+        void setRange(rapidjson::Value::ConstValueIterator current, rapidjson::Value::ConstValueIterator end)
+        {
+            current_in_array = &*current;
+            end_of_array = &*end;
+            is_object_member = false;
+        }
+
+        void setRange(rapidjson::Value::ConstMemberIterator current, rapidjson::Value::ConstMemberIterator end)
+        {
+            current_in_object = &*current;
+            end_of_object = &*end;
+            is_object_member = true;
+        }
+
+        static StringRef getKeyImpl(const rapidjson::GenericMember<rapidjson::UTF8<>, rapidjson::MemoryPoolAllocator<>> * member)
+        {
+            const auto & name = member->name;
+            return {name.GetString(), name.GetStringLength()};
+        }
+
+        const rapidjson::Value * value = nullptr;
+        bool is_object_member = false;
+
+        union
+        {
+            const rapidjson::GenericMember<rapidjson::UTF8<>, rapidjson::MemoryPoolAllocator<>> * current_in_object;
+            const rapidjson::Value * current_in_array;
+        };
+        union
+        {
+            const rapidjson::GenericMember<rapidjson::UTF8<>, rapidjson::MemoryPoolAllocator<>> * end_of_object;
+            const rapidjson::Value * end_of_array;
+        };
+    };
+
+    Iterator getRoot() { return Iterator{document}; }
+
+    static bool isInt64(const Iterator & it) { return it.isInt64(); }
+    static bool isUInt64(const Iterator & it) { return it.isUInt64(); }
+    static bool isDouble(const Iterator & it) { return it.isDouble(); }
+    static bool isBool(const Iterator & it) { return it.isBool(); }
+    static bool isString(const Iterator & it) { return it.isString(); }
+    static bool isArray(const Iterator & it) { return it.isArray(); }
+    static bool isObject(const Iterator & it) { return it.isObject(); }
+    static bool isNull(const Iterator & it) { return it.isNull(); }
+
+    static Int64 getInt64(const Iterator & it) { return it.getInt64(); }
+    static UInt64 getUInt64(const Iterator & it) { return it.getUInt64(); }
+    static double getDouble(const Iterator & it) { return it.getDouble(); }
+    static bool getBool(const Iterator & it) { return it.getBool(); }
+    static StringRef getString(const Iterator & it) { return it.getString(); }
+
+    static size_t sizeOfArray(const Iterator & it) { return it.sizeOfArray(); }
+    static bool firstArrayElement(Iterator & it) { return it.arrayElementByIndex(0); }
+    static bool arrayElementByIndex(Iterator & it, size_t index) { return it.arrayElementByIndex(index); }
+    static bool nextArrayElement(Iterator & it) { return it.nextArrayElement(); }
+
+    static size_t sizeOfObject(const Iterator & it) { return it.sizeOfObject(); }
+    static bool firstObjectMember(Iterator & it) { return it.objectMemberByIndex(0); }
+    static bool firstObjectMember(Iterator & it, StringRef & first_key) { return it.objectMemberByIndex(0, first_key); }
+    static bool objectMemberByIndex(Iterator & it, size_t index) { return it.objectMemberByIndex(index); }
+    static bool objectMemberByName(Iterator & it, const StringRef & name) { return it.objectMemberByName(name); }
+    static bool nextObjectMember(Iterator & it) { return it.nextObjectMember(); }
+    static bool nextObjectMember(Iterator & it, StringRef & next_key) { return it.nextObjectMember(next_key); }
+    static bool isObjectMember(const Iterator & it) { return it.isObjectMember(); }
+    static StringRef getKey(const Iterator & it) { return it.getKey(); }
+
+private:
+    rapidjson::Document document;
+};
+
+}
+#endif

dbms/src/Functions/SimdJSONParser.h

@@ -0,0 +1,150 @@
+#pragma once
+
+#include <Common/config.h>
+#if USE_SIMDJSON
+
+#include <common/StringRef.h>
+#include <Common/Exception.h>
+#include <Core/Types.h>
+
+#ifdef __clang__
+    #pragma clang diagnostic push
+    #pragma clang diagnostic ignored "-Wold-style-cast"
+    #pragma clang diagnostic ignored "-Wnewline-eof"
+#endif
+
+#include <simdjson/jsonparser.h>
+
+#ifdef __clang__
+    #pragma clang diagnostic pop
+#endif
+
+
+namespace DB
+{
+namespace ErrorCodes
+{
+    extern const int CANNOT_ALLOCATE_MEMORY;
+}
+
+/// This class can be used as an argument for the template class FunctionJSON.
+/// It provides ability to parse JSONs using simdjson library.
+struct SimdJSONParser
+{
+    static constexpr bool need_preallocate = true;
+
+    void preallocate(size_t max_size)
+    {
+        if (!pj.allocateCapacity(max_size))
+            throw Exception{"Can not allocate memory for " + std::to_string(max_size) + " units when parsing JSON",
+                            ErrorCodes::CANNOT_ALLOCATE_MEMORY};
+    }
+
+    bool parse(const StringRef & json) { return !json_parse(json.data, json.size, pj); }
+
+    using Iterator = ParsedJson::iterator;
+    Iterator getRoot() { return Iterator{pj}; }
+
+    static bool isInt64(const Iterator & it) { return it.is_integer(); }
+    static bool isUInt64(const Iterator &) { return false; /* See https://github.com/lemire/simdjson/issues/68 */ }
+    static bool isDouble(const Iterator & it) { return it.is_double(); }
+    static bool isString(const Iterator & it) { return it.is_string(); }
+    static bool isArray(const Iterator & it) { return it.is_array(); }
+    static bool isObject(const Iterator & it) { return it.is_object(); }
+    static bool isBool(const Iterator & it) { return it.get_type() == 't' || it.get_type() == 'f'; }
+    static bool isNull(const Iterator & it) { return it.is_null(); }
+
+    static Int64 getInt64(const Iterator & it) { return it.get_integer(); }
+    static UInt64 getUInt64(const Iterator &) { return 0; /* isUInt64() never returns true */ }
+    static double getDouble(const Iterator & it) { return it.get_double(); }
+    static bool getBool(const Iterator & it) { return it.get_type() == 't'; }
+    static StringRef getString(const Iterator & it) { return StringRef{it.get_string(), it.get_string_length()}; }
+
+    static size_t sizeOfArray(const Iterator & it)
+    {
+        size_t size = 0;
+        Iterator it2 = it;
+        if (it2.down())
+        {
+            do
+                ++size;
+            while (it2.next());
+        }
+        return size;
+    }
+
+    static bool firstArrayElement(Iterator & it) { return it.down(); }
+
+    static bool arrayElementByIndex(Iterator & it, size_t index)
+    {
+        if (!it.down())
+            return false;
+        while (index--)
+            if (!it.next())
+                return false;
+        return true;
+    }
+
+    static bool nextArrayElement(Iterator & it) { return it.next(); }
+
+    static size_t sizeOfObject(const Iterator & it)
+    {
+        size_t size = 0;
+        Iterator it2 = it;
+        if (it2.down())
+        {
+            do
+                ++size;
+            while (it2.next() && it2.next());
+        }
+        return size;
+    }
+
+    static bool firstObjectMember(Iterator & it) { return it.down() && it.next(); }
+
+    static bool firstObjectMember(Iterator & it, StringRef & first_key)
+    {
+        if (!it.down())
+            return false;
+        first_key.data = it.get_string();
+        first_key.size = it.get_string_length();
+        return it.next();
+    }
+
+    static bool objectMemberByIndex(Iterator & it, size_t index)
+    {
+        if (!it.down())
+            return false;
+        while (index--)
+            if (!it.next() || !it.next())
+                return false;
+        return it.next();
+    }
+
+    static bool objectMemberByName(Iterator & it, const StringRef & name) { return it.move_to_key(name.data); }
+    static bool nextObjectMember(Iterator & it) { return it.next() && it.next(); }
+
+    static bool nextObjectMember(Iterator & it, StringRef & next_key)
+    {
+        if (!it.next())
+            return false;
+        next_key.data = it.get_string();
+        next_key.size = it.get_string_length();
+        return it.next();
+    }
+
+    static bool isObjectMember(const Iterator & it) { return it.get_scope_type() == '{'; }
+
+    static StringRef getKey(const Iterator & it)
+    {
+        Iterator it2 = it;
+        it2.prev();
+        return StringRef{it2.get_string(), it2.get_string_length()};
+    }
+
+private:
+    ParsedJson pj;
+};
+
+}
+#endif

dbms/src/Functions/isValidUTF8.cpp

@@ -315,13 +315,13 @@ SOFTWARE.
     }
 };
 
-struct NameValidUTF8
+struct NameIsValidUTF8
 {
     static constexpr auto name = "isValidUTF8";
 };
-using FunctionValidUTF8 = FunctionStringOrArrayToT<ValidUTF8Impl, NameValidUTF8, UInt8>;
+using FunctionValidUTF8 = FunctionStringOrArrayToT<ValidUTF8Impl, NameIsValidUTF8, UInt8>;
 
-void registerFunctionValidUTF8(FunctionFactory & factory)
+void registerFunctionIsValidUTF8(FunctionFactory & factory)
 {
     factory.registerFunction<FunctionValidUTF8>();
 }

dbms/src/Functions/registerFunctionsString.cpp

@@ -9,7 +9,8 @@ void registerFunctionEmpty(FunctionFactory &);
 void registerFunctionNotEmpty(FunctionFactory &);
 void registerFunctionLength(FunctionFactory &);
 void registerFunctionLengthUTF8(FunctionFactory &);
-void registerFunctionValidUTF8(FunctionFactory &);
+void registerFunctionIsValidUTF8(FunctionFactory &);
+void registerFunctionToValidUTF8(FunctionFactory &);
 void registerFunctionLower(FunctionFactory &);
 void registerFunctionUpper(FunctionFactory &);
 void registerFunctionLowerUTF8(FunctionFactory &);
@@ -36,7 +37,8 @@ void registerFunctionsString(FunctionFactory & factory)
     registerFunctionNotEmpty(factory);
     registerFunctionLength(factory);
     registerFunctionLengthUTF8(factory);
-    registerFunctionValidUTF8(factory);
+    registerFunctionIsValidUTF8(factory);
+    registerFunctionToValidUTF8(factory);
     registerFunctionLower(factory);
     registerFunctionUpper(factory);
     registerFunctionLowerUTF8(factory);

dbms/src/Functions/toValidUTF8.cpp

@@ -0,0 +1,144 @@
+#include <DataTypes/DataTypeString.h>
+#include <Functions/FunctionFactory.h>
+#include <Functions/FunctionStringToString.h>
+#include <IO/WriteBufferFromVector.h>
+#include <IO/WriteBufferValidUTF8.h>
+#include <IO/WriteHelpers.h>
+#include <Poco/UTF8Encoding.h>
+
+#include <string_view>
+
+#ifdef __SSE2__
+#    include <emmintrin.h>
+#endif
+
+namespace DB
+{
+namespace ErrorCodes
+{
+    extern const int ILLEGAL_COLUMN;
+}
+
+extern const UInt8 length_of_utf8_sequence[256];
+
+struct ToValidUTF8Impl
+{
+    static void toValidUTF8One(const char * begin, const char * end, WriteBuffer & write_buffer)
+    {
+        static constexpr std::string_view replacement = "\xEF\xBF\xBD";
+
+        const char * p = begin;
+        const char * valid_start = begin;
+
+        /// The last recorded character was `replacement`.
+        bool just_put_replacement = false;
+
+        auto put_valid = [&write_buffer, &just_put_replacement](const char * data, size_t len)
+        {
+            if (len == 0)
+                return;
+            just_put_replacement = false;
+            write_buffer.write(data, len);
+        };
+
+        auto put_replacement = [&write_buffer, &just_put_replacement]()
+        {
+            if (just_put_replacement)
+                return;
+            just_put_replacement = true;
+            write_buffer.write(replacement.data(), replacement.size());
+        };
+
+        while (p < end)
+        {
+#ifdef __SSE2__
+            /// Fast skip of ASCII
+            static constexpr size_t SIMD_BYTES = 16;
+            const char * simd_end = p + (end - p) / SIMD_BYTES * SIMD_BYTES;
+
+            while (p < simd_end && !_mm_movemask_epi8(_mm_loadu_si128(reinterpret_cast<const __m128i *>(p))))
+                p += SIMD_BYTES;
+
+            if (!(p < end))
+                break;
+#endif
+
+            size_t len = length_of_utf8_sequence[static_cast<unsigned char>(*p)];
+
+            if (len > 4)
+            {
+                /// Invalid start of sequence. Skip one byte.
+                put_valid(valid_start, p - valid_start);
+                put_replacement();
+                ++p;
+                valid_start = p;
+            }
+            else if (p + len > end)
+            {
+                /// Sequence was not fully written to this buffer.
+                break;
+            }
+            else if (Poco::UTF8Encoding::isLegal(reinterpret_cast<const unsigned char *>(p), len))
+            {
+                /// Valid sequence.
+                p += len;
+            }
+            else
+            {
+                /// Invalid sequence. Skip just first byte.
+                put_valid(valid_start, p - valid_start);
+                put_replacement();
+                ++p;
+                valid_start = p;
+            }
+        }
+
+        put_valid(valid_start, p - valid_start);
+
+        if (p != end)
+            put_replacement();
+    }
+
+    static void vector(
+        const ColumnString::Chars & data,
+        const ColumnString::Offsets & offsets,
+        ColumnString::Chars & res_data,
+        ColumnString::Offsets & res_offsets)
+    {
+        const size_t offsets_size = offsets.size();
+        /// It can be larger than that, but we believe it is unlikely to happen.
+        res_data.resize(data.size());
+        res_offsets.resize(offsets_size);
+
+        size_t prev_offset = 0;
+        WriteBufferFromVector<ColumnString::Chars> write_buffer(res_data);
+        for (size_t i = 0; i < offsets_size; ++i)
+        {
+            const char * haystack_data = reinterpret_cast<const char *>(&data[prev_offset]);
+            const size_t haystack_size = offsets[i] - prev_offset - 1;
+            toValidUTF8One(haystack_data, haystack_data + haystack_size, write_buffer);
+            writeChar(0, write_buffer);
+            res_offsets[i] = write_buffer.count();
+            prev_offset = offsets[i];
+        }
+        write_buffer.finish();
+    }
+
+    static void vector_fixed(const ColumnString::Chars &, size_t, ColumnString::Chars &)
+    {
+        throw Exception("Column of type FixedString is not supported by toValidUTF8 function", ErrorCodes::ILLEGAL_COLUMN);
+    }
+};
+
+struct NameToValidUTF8
+{
+    static constexpr auto name = "toValidUTF8";
+};
+using FunctionToValidUTF8 = FunctionStringToString<ToValidUTF8Impl, NameToValidUTF8>;
+
+void registerFunctionToValidUTF8(FunctionFactory & factory)
+{
+    factory.registerFunction<FunctionToValidUTF8>();
+}
+
+}

dbms/src/IO/WriteBufferFromVector.h

@@ -38,18 +38,29 @@ private:
         working_buffer = internal_buffer;
     }
 
+    static constexpr size_t initial_size = 32;
+
 public:
     WriteBufferFromVector(VectorType & vector_)
         : WriteBuffer(reinterpret_cast<Position>(vector_.data()), vector_.size()), vector(vector_)
     {
         if (vector.empty())
         {
-            static constexpr size_t initial_size = 32;
             vector.resize(initial_size);
             set(reinterpret_cast<Position>(vector.data()), vector.size());
         }
     }
 
+    /// Append to vector instead of rewrite.
+    struct AppendModeTag {};
+    WriteBufferFromVector(VectorType & vector_, AppendModeTag)
+        : WriteBuffer(nullptr, 0), vector(vector_)
+    {
+        size_t old_size = vector.size();
+        vector.resize(vector.capacity() < initial_size ? initial_size : vector.capacity());
+        set(reinterpret_cast<Position>(vector.data() + old_size), (vector.size() - old_size) * sizeof(typename VectorType::value_type));
+    }
+
     void finish()
     {
         if (is_finished)

dbms/src/IO/WriteBufferValidUTF8.cpp

@@ -12,26 +12,23 @@ namespace DB
 
 const size_t WriteBufferValidUTF8::DEFAULT_SIZE = 4096;
 
-namespace
+/** Index into the table below with the first byte of a UTF-8 sequence to
+  * get the number of trailing bytes that are supposed to follow it.
+  * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is
+  * left as-is for anyone who may want to do such conversion, which was
+  * allowed in earlier algorithms.
+  */
+extern const UInt8 length_of_utf8_sequence[256] =
 {
-    /** Index into the table below with the first byte of a UTF-8 sequence to
-      * get the number of trailing bytes that are supposed to follow it.
-      * Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is
-      * left as-is for anyone who may want to do such conversion, which was
-      * allowed in earlier algorithms.
-      */
-    const UInt8 length_of_utf8_sequence[256] =
-    {
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-        2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
-        3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, 4,4,4,4,4,4,4,4,5,5,5,5,6,6,6,6
-    };
-}
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+    2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+    3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, 4,4,4,4,4,4,4,4,5,5,5,5,6,6,6,6
+};
 
 
 WriteBufferValidUTF8::WriteBufferValidUTF8(

dbms/src/Interpreters/ActionLocksManager.h

@@ -1,14 +1,16 @@
 #pragma once
+
 #include <Core/Types.h>
+#include <Storages/IStorage_fwd.h>
 #include <Common/ActionLock.h>
-#include <unordered_map>
+
 #include <mutex>
+#include <unordered_map>
 
 
 namespace DB
 {
 
-class IStorage;
 class Context;
 
 /// Holds ActionLocks for tables

dbms/src/Interpreters/Aggregator.h

@@ -18,7 +18,7 @@
 #include <Common/LRUCache.h>
 #include <Common/ColumnsHashing.h>
 
-#include <DataStreams/IBlockInputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <DataStreams/SizeLimits.h>
 
 #include <Interpreters/AggregateDescription.h>

dbms/src/Interpreters/ClusterProxy/IStreamFactory.h

@@ -1,9 +1,8 @@
 #pragma once
 
+#include <Client/ConnectionPool.h>
 #include <Interpreters/Cluster.h>
 #include <Parsers/IAST.h>
-#include <Storages/IStorage.h>
-#include <Client/ConnectionPool.h>
 
 namespace DB
 {

dbms/src/Interpreters/ClusterProxy/SelectStreamFactory.h

@@ -1,8 +1,8 @@
 #pragma once
 
-#include <Interpreters/ClusterProxy/IStreamFactory.h>
 #include <Core/QueryProcessingStage.h>
-#include <Storages/IStorage.h>
+#include <Interpreters/ClusterProxy/IStreamFactory.h>
+#include <Storages/IStorage_fwd.h>
 
 namespace DB
 {

dbms/src/Interpreters/ClusterProxy/executeQuery.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <Parsers/IAST.h>
-#include <Storages/IStorage.h>
 #include <Interpreters/Cluster.h>
 
 namespace DB

dbms/src/Interpreters/Context.h

@@ -2,14 +2,16 @@
 
 #include <Core/Block.h>
 #include <Core/NamesAndTypes.h>
-#include <Core/Types.h>
-#include <Interpreters/ClientInfo.h>
 #include <Core/Settings.h>
+#include <Core/Types.h>
+#include <DataStreams/IBlockStream_fwd.h>
+#include <Interpreters/ClientInfo.h>
 #include <Parsers/IAST_fwd.h>
 #include <Common/LRUCache.h>
 #include <Common/MultiVersion.h>
 #include <Common/ThreadPool.h>
 #include <Common/config.h>
+#include <Storages/IStorage_fwd.h>
 
 #include <atomic>
 #include <chrono>
@@ -65,14 +67,7 @@ struct MergeTreeSettings;
 class IDatabase;
 class DDLGuard;
 class DDLWorker;
-class IStorage;
 class ITableFunction;
-using StoragePtr = std::shared_ptr<IStorage>;
-using Tables = std::map<String, StoragePtr>;
-class IBlockInputStream;
-class IBlockOutputStream;
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-using BlockOutputStreamPtr = std::shared_ptr<IBlockOutputStream>;
 class Block;
 class ActionLocksManager;
 using ActionLocksManagerPtr = std::shared_ptr<ActionLocksManager>;

dbms/src/Interpreters/ExecuteScalarSubqueriesVisitor.cpp

@@ -10,6 +10,7 @@
 #include <Interpreters/InterpreterSelectWithUnionQuery.h>
 #include <Interpreters/ExecuteScalarSubqueriesVisitor.h>
 
+#include <DataStreams/IBlockInputStream.h>
 #include <DataTypes/DataTypeAggregateFunction.h>
 
 namespace DB

dbms/src/Interpreters/ExpressionActions.h

@@ -1,15 +1,16 @@
 #pragma once
 
-#include <Interpreters/Context.h>
-#include <Common/config.h>
-#include <Common/SipHash.h>
-#include <Core/Settings.h>
-#include <Core/Names.h>
-#include <Core/ColumnWithTypeAndName.h>
 #include <Core/Block.h>
+#include <Core/ColumnWithTypeAndName.h>
+#include <Core/Names.h>
+#include <Core/Settings.h>
+#include <DataStreams/IBlockStream_fwd.h>
+#include <Interpreters/Context.h>
+#include <Common/SipHash.h>
+#include <Common/config.h>
 
-#include <unordered_set>
 #include <unordered_map>
+#include <unordered_set>
 
 
 namespace DB
@@ -37,9 +38,6 @@ using FunctionBuilderPtr = std::shared_ptr<IFunctionBuilder>;
 class IDataType;
 using DataTypePtr = std::shared_ptr<const IDataType>;
 
-class IBlockInputStream;
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-
 class ExpressionActions;
 
 /** Action on the block.

dbms/src/Interpreters/ExpressionAnalyzer.cpp

@@ -39,6 +39,7 @@
 #include <Storages/StorageJoin.h>
 
 #include <DataStreams/copyData.h>
+#include <DataStreams/IBlockInputStream.h>
 
 #include <Dictionaries/IDictionary.h>
 

dbms/src/Interpreters/ExpressionAnalyzer.h

@@ -1,10 +1,12 @@
 #pragma once
 
+#include <Core/Settings.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <Interpreters/ActionsVisitor.h>
 #include <Interpreters/AggregateDescription.h>
-#include <Core/Settings.h>
 #include <Interpreters/SyntaxAnalyzer.h>
 #include <Parsers/IAST_fwd.h>
+#include <Storages/IStorage_fwd.h>
 
 
 namespace DB
@@ -19,13 +21,6 @@ using ExpressionActionsPtr = std::shared_ptr<ExpressionActions>;
 
 struct ASTTableJoin;
 
-class IBlockInputStream;
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
-using Tables = std::map<String, StoragePtr>;
-
 class ASTFunction;
 class ASTExpressionList;
 class ASTSelectQuery;

dbms/src/Interpreters/InJoinSubqueriesPreprocessor.h

@@ -1,16 +1,17 @@
 #pragma once
 
+#include <Core/SettingsCommon.h>
+#include <Core/Types.h>
+#include <Parsers/IAST_fwd.h>
+#include <Storages/IStorage_fwd.h>
+
 #include <string>
 #include <memory>
-#include <Core/Types.h>
-#include <Core/SettingsCommon.h>
-#include <Parsers/IAST_fwd.h>
 
 
 namespace DB
 {
 
-class IStorage;
 class ASTSelectQuery;
 class Context;
 

dbms/src/Interpreters/InterpreterCheckQuery.h

@@ -1,7 +1,8 @@
 #pragma once
 
+#include <Core/Block.h>
 #include <Interpreters/IInterpreter.h>
-#include <Parsers/IAST.h>
+#include <Parsers/IAST_fwd.h>
 
 namespace DB
 {

dbms/src/Interpreters/InterpreterCreateQuery.h

@@ -2,6 +2,7 @@
 
 #include <Interpreters/IInterpreter.h>
 #include <Storages/ColumnsDescription.h>
+#include <Storages/IStorage_fwd.h>
 #include <Storages/IndicesDescription.h>
 #include <Storages/ConstraintsDescription.h>
 #include <Common/ThreadPool.h>
@@ -13,8 +14,6 @@ namespace DB
 class Context;
 class ASTCreateQuery;
 class ASTExpressionList;
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
 
 
 /** Allows to create new table or database,

dbms/src/Interpreters/InterpreterKillQueryQuery.h

@@ -1,7 +1,8 @@
 #pragma once
 
+#include <Core/Block.h>
 #include <Interpreters/IInterpreter.h>
-#include <Parsers/IAST.h>
+#include <Parsers/IAST_fwd.h>
 
 
 namespace DB

dbms/src/Interpreters/InterpreterSelectQuery.h

@@ -4,13 +4,14 @@
 
 #include <Core/QueryProcessingStage.h>
 #include <Parsers/ASTSelectQuery.h>
-#include <DataStreams/IBlockInputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/ExpressionActions.h>
 #include <Interpreters/ExpressionAnalyzer.h>
 #include <Interpreters/IInterpreter.h>
 #include <Interpreters/SelectQueryOptions.h>
 #include <Storages/SelectQueryInfo.h>
+#include <Storages/TableStructureLockHolder.h>
 
 
 namespace Poco { class Logger; }

dbms/src/Interpreters/InterpreterSystemQuery.h

@@ -2,16 +2,16 @@
 
 #include <Interpreters/IInterpreter.h>
 #include <Parsers/IAST_fwd.h>
+#include <Storages/IStorage_fwd.h>
 
 
+namespace Poco { class Logger; }
+
 namespace DB
 {
 
 class Context;
 class ASTSystemQuery;
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
-
 
 class InterpreterSystemQuery : public IInterpreter
 {

dbms/src/Interpreters/Join.h

@@ -18,7 +18,7 @@
 #include <Columns/ColumnFixedString.h>
 
 #include <DataStreams/SizeLimits.h>
-#include <DataStreams/IBlockInputStream.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <variant>
 #include <common/constexpr_helpers.h>
 

dbms/src/Interpreters/MutationsInterpreter.h

@@ -1,10 +1,10 @@
 #pragma once
 
-#include <Interpreters/ExpressionAnalyzer.h>
-#include <Interpreters/ExpressionActions.h>
-#include <Interpreters/InterpreterSelectQuery.h>
 #include <DataStreams/IBlockInputStream.h>
-#include <Storages/IStorage.h>
+#include <Interpreters/ExpressionActions.h>
+#include <Interpreters/ExpressionAnalyzer.h>
+#include <Interpreters/InterpreterSelectQuery.h>
+#include <Storages/IStorage_fwd.h>
 #include <Storages/MutationCommands.h>
 
 

dbms/src/Interpreters/ProcessList.h

@@ -1,25 +1,28 @@
 #pragma once
 
-#include <map>
+
+#include <Core/Defines.h>
+#include <DataStreams/BlockIO.h>
+#include <IO/Progress.h>
+#include <Interpreters/CancellationCode.h>
+#include <Interpreters/ClientInfo.h>
+#include <Interpreters/QueryPriorities.h>
+#include <Storages/IStorage_fwd.h>
+#include <Poco/Condition.h>
+#include <Common/CurrentMetrics.h>
+#include <Common/CurrentThread.h>
+#include <Common/MemoryTracker.h>
+#include <Common/ProfileEvents.h>
+#include <Common/Stopwatch.h>
+#include <Common/Throttler.h>
+
+#include <condition_variable>
 #include <list>
+#include <map>
 #include <memory>
 #include <mutex>
-#include <condition_variable>
-#include <unordered_map>
 #include <shared_mutex>
-#include <Poco/Condition.h>
-#include <Core/Defines.h>
-#include <IO/Progress.h>
-#include <Common/Stopwatch.h>
-#include <Common/MemoryTracker.h>
-#include <Common/CurrentMetrics.h>
-#include <Common/ProfileEvents.h>
-#include <Common/Throttler.h>
-#include <Common/CurrentThread.h>
-#include <Interpreters/QueryPriorities.h>
-#include <Interpreters/ClientInfo.h>
-#include <Interpreters/CancellationCode.h>
-#include <DataStreams/BlockIO.h>
+#include <unordered_map>
 
 
 namespace CurrentMetrics
@@ -30,9 +33,6 @@ namespace CurrentMetrics
 namespace DB
 {
 
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
-using Tables = std::map<String, StoragePtr>;
 class Context;
 struct Settings;
 class IAST;

dbms/src/Interpreters/SyntaxAnalyzer.h

@@ -1,15 +1,13 @@
 #pragma once
 
-#include <Interpreters/AnalyzedJoin.h>
 #include <Interpreters/Aliases.h>
+#include <Interpreters/AnalyzedJoin.h>
 #include <Interpreters/SelectQueryOptions.h>
+#include <Storages/IStorage_fwd.h>
 
 namespace DB
 {
 
-class IStorage;
-using StoragePtr = std::shared_ptr<IStorage>;
-
 NameSet removeDuplicateColumns(NamesAndTypesList & columns);
 
 struct SyntaxAnalyzerResult

dbms/src/Parsers/ASTFunction.cpp

@@ -2,6 +2,7 @@
 #include <Parsers/ASTLiteral.h>
 #include <Parsers/ASTFunction.h>
 #include <Parsers/ASTWithAlias.h>
+#include <Parsers/ASTSubquery.h>
 #include <IO/WriteHelpers.h>
 #include <IO/WriteBufferFromString.h>
 
@@ -141,7 +142,7 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
             }
         }
 
-        /** need_parens - do I need parentheses around the expression with the operator.
+        /** need_parens - do we need parentheses around the expression with the operator.
           * They are needed only if this expression is included in another expression with the operator.
           */
 
@@ -182,7 +183,22 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
                         && (name == "like" || name == "notLike")
                         && highlightStringLiteralWithMetacharacters(arguments->children[1], settings, "%_");
 
-                    if (!special_hilite)
+                    /// Format x IN 1 as x IN (1): put parens around rhs even if there is a single element in set.
+                    const auto * second_arg_func = arguments->children[1]->as<ASTFunction>();
+                    const auto * second_arg_literal = arguments->children[1]->as<ASTLiteral>();
+                    bool extra_parents_around_in_rhs = (name == "in" || name == "notIn" || name == "globalIn" || name == "globalNotIn")
+                        && !(second_arg_func && second_arg_func->name == "tuple")
+                        && !(second_arg_literal && second_arg_literal->value.getType() == Field::Types::Tuple)
+                        && !arguments->children[1]->as<ASTSubquery>();
+
+                    if (extra_parents_around_in_rhs)
+                    {
+                        settings.ostr << '(';
+                        arguments->children[1]->formatImpl(settings, state, nested_dont_need_parens);
+                        settings.ostr << ')';
+                    }
+
+                    if (!special_hilite && !extra_parents_around_in_rhs)
                         arguments->children[1]->formatImpl(settings, state, nested_need_parens);
 
                     if (frame.need_parens)

dbms/src/Parsers/ParserQuery.h

@@ -10,7 +10,7 @@ class ParserQuery : public IParserBase
 {
 private:
     const char * end;
-    bool enable_explain;
+    bool enable_explain;    /// Allow queries prefixed with AST and ANALYZE for development purposes.
 
     const char * getName() const override { return "Query"; }
     bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;

dbms/src/Storages/AlterCommands.h

@@ -3,6 +3,7 @@
 #include <optional>
 #include <Core/NamesAndTypes.h>
 #include <Storages/ColumnsDescription.h>
+#include <Storages/IStorage_fwd.h>
 #include <Storages/IndicesDescription.h>
 
 
@@ -89,7 +90,6 @@ struct AlterCommand
     bool isMutable() const;
 };
 
-class IStorage;
 class Context;
 
 class AlterCommands : public std::vector<AlterCommand>

dbms/src/Storages/IStorage.cpp

@@ -1,11 +1,331 @@
 #include <Storages/IStorage.h>
+
 #include <Storages/AlterCommands.h>
 
+#include <sparsehash/dense_hash_map>
+#include <sparsehash/dense_hash_set>
+
 
 namespace DB
 {
 
-void IStorage::alter(const AlterCommands & params, const String & database_name, const String & table_name, const Context & context, TableStructureWriteLockHolder & table_lock_holder)
+namespace ErrorCodes
+{
+    extern const int COLUMN_QUERIED_MORE_THAN_ONCE;
+    extern const int DUPLICATE_COLUMN;
+    extern const int EMPTY_LIST_OF_COLUMNS_PASSED;
+    extern const int EMPTY_LIST_OF_COLUMNS_QUERIED;
+    extern const int NO_SUCH_COLUMN_IN_TABLE;
+    extern const int NOT_FOUND_COLUMN_IN_BLOCK;
+    extern const int TYPE_MISMATCH;
+}
+
+IStorage::IStorage(ColumnsDescription columns_)
+{
+    setColumns(std::move(columns_));
+}
+
+const ColumnsDescription & IStorage::getColumns() const
+{
+    return columns;
+}
+
+void IStorage::setColumns(ColumnsDescription columns_)
+{
+    if (columns_.getOrdinary().empty())
+        throw Exception("Empty list of columns passed", ErrorCodes::EMPTY_LIST_OF_COLUMNS_PASSED);
+    columns = std::move(columns_);
+}
+
+const IndicesDescription & IStorage::getIndices() const
+{
+    return indices;
+}
+
+void IStorage::setIndices(IndicesDescription indices_)
+{
+    indices = std::move(indices_);
+}
+
+NameAndTypePair IStorage::getColumn(const String & column_name) const
+{
+    /// By default, we assume that there are no virtual columns in the storage.
+    return getColumns().getPhysical(column_name);
+}
+
+bool IStorage::hasColumn(const String & column_name) const
+{
+    /// By default, we assume that there are no virtual columns in the storage.
+    return getColumns().hasPhysical(column_name);
+}
+
+Block IStorage::getSampleBlock() const
+{
+    Block res;
+
+    for (const auto & column : getColumns().getAllPhysical())
+        res.insert({column.type->createColumn(), column.type, column.name});
+
+    return res;
+}
+
+Block IStorage::getSampleBlockNonMaterialized() const
+{
+    Block res;
+
+    for (const auto & column : getColumns().getOrdinary())
+        res.insert({column.type->createColumn(), column.type, column.name});
+
+    return res;
+}
+
+Block IStorage::getSampleBlockForColumns(const Names & column_names) const
+{
+    Block res;
+
+    NamesAndTypesList all_columns = getColumns().getAll();
+    std::unordered_map<String, DataTypePtr> columns_map;
+    for (const auto & elem : all_columns)
+        columns_map.emplace(elem.name, elem.type);
+
+    for (const auto & name : column_names)
+    {
+        auto it = columns_map.find(name);
+        if (it != columns_map.end())
+        {
+            res.insert({it->second->createColumn(), it->second, it->first});
+        }
+        else
+        {
+            /// Virtual columns.
+            NameAndTypePair elem = getColumn(name);
+            res.insert({elem.type->createColumn(), elem.type, elem.name});
+        }
+    }
+
+    return res;
+}
+
+namespace
+{
+    using NamesAndTypesMap = GOOGLE_NAMESPACE::dense_hash_map<StringRef, const IDataType *, StringRefHash>;
+    using UniqueStrings = GOOGLE_NAMESPACE::dense_hash_set<StringRef, StringRefHash>;
+
+    String listOfColumns(const NamesAndTypesList & available_columns)
+    {
+        std::stringstream ss;
+        for (auto it = available_columns.begin(); it != available_columns.end(); ++it)
+        {
+            if (it != available_columns.begin())
+                ss << ", ";
+            ss << it->name;
+        }
+        return ss.str();
+    }
+
+    NamesAndTypesMap getColumnsMap(const NamesAndTypesList & columns)
+    {
+        NamesAndTypesMap res;
+        res.set_empty_key(StringRef());
+
+        for (const auto & column : columns)
+            res.insert({column.name, column.type.get()});
+
+        return res;
+    }
+
+    UniqueStrings initUniqueStrings()
+    {
+        UniqueStrings strings;
+        strings.set_empty_key(StringRef());
+        return strings;
+    }
+}
+
+void IStorage::check(const Names & column_names) const
+{
+    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
+    const String list_of_columns = listOfColumns(available_columns);
+
+    if (column_names.empty())
+        throw Exception("Empty list of columns queried. There are columns: " + list_of_columns, ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED);
+
+    const auto columns_map = getColumnsMap(available_columns);
+
+    auto unique_names = initUniqueStrings();
+    for (const auto & name : column_names)
+    {
+        if (columns_map.end() == columns_map.find(name))
+            throw Exception(
+                "There is no column with name " + name + " in table. There are columns: " + list_of_columns,
+                ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
+
+        if (unique_names.end() != unique_names.find(name))
+            throw Exception("Column " + name + " queried more than once", ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
+        unique_names.insert(name);
+    }
+}
+
+void IStorage::check(const NamesAndTypesList & provided_columns) const
+{
+    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
+    const auto columns_map = getColumnsMap(available_columns);
+
+    auto unique_names = initUniqueStrings();
+    for (const NameAndTypePair & column : provided_columns)
+    {
+        auto it = columns_map.find(column.name);
+        if (columns_map.end() == it)
+            throw Exception(
+                "There is no column with name " + column.name + ". There are columns: " + listOfColumns(available_columns),
+                ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
+
+        if (!column.type->equals(*it->second))
+            throw Exception(
+                "Type mismatch for column " + column.name + ". Column has type " + it->second->getName() + ", got type "
+                    + column.type->getName(),
+                ErrorCodes::TYPE_MISMATCH);
+
+        if (unique_names.end() != unique_names.find(column.name))
+            throw Exception("Column " + column.name + " queried more than once", ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
+        unique_names.insert(column.name);
+    }
+}
+
+void IStorage::check(const NamesAndTypesList & provided_columns, const Names & column_names) const
+{
+    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
+    const auto available_columns_map = getColumnsMap(available_columns);
+    const auto & provided_columns_map = getColumnsMap(provided_columns);
+
+    if (column_names.empty())
+        throw Exception(
+            "Empty list of columns queried. There are columns: " + listOfColumns(available_columns),
+            ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED);
+
+    auto unique_names = initUniqueStrings();
+    for (const String & name : column_names)
+    {
+        auto it = provided_columns_map.find(name);
+        if (provided_columns_map.end() == it)
+            continue;
+
+        auto jt = available_columns_map.find(name);
+        if (available_columns_map.end() == jt)
+            throw Exception(
+                "There is no column with name " + name + ". There are columns: " + listOfColumns(available_columns),
+                ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
+
+        if (!it->second->equals(*jt->second))
+            throw Exception(
+                "Type mismatch for column " + name + ". Column has type " + jt->second->getName() + ", got type " + it->second->getName(),
+                ErrorCodes::TYPE_MISMATCH);
+
+        if (unique_names.end() != unique_names.find(name))
+            throw Exception("Column " + name + " queried more than once", ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
+        unique_names.insert(name);
+    }
+}
+
+void IStorage::check(const Block & block, bool need_all) const
+{
+    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
+    const auto columns_map = getColumnsMap(available_columns);
+
+    NameSet names_in_block;
+
+    block.checkNumberOfRows();
+
+    for (const auto & column : block)
+    {
+        if (names_in_block.count(column.name))
+            throw Exception("Duplicate column " + column.name + " in block", ErrorCodes::DUPLICATE_COLUMN);
+
+        names_in_block.insert(column.name);
+
+        auto it = columns_map.find(column.name);
+        if (columns_map.end() == it)
+            throw Exception(
+                "There is no column with name " + column.name + ". There are columns: " + listOfColumns(available_columns),
+                ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
+
+        if (!column.type->equals(*it->second))
+            throw Exception(
+                "Type mismatch for column " + column.name + ". Column has type " + it->second->getName() + ", got type "
+                    + column.type->getName(),
+                ErrorCodes::TYPE_MISMATCH);
+    }
+
+    if (need_all && names_in_block.size() < columns_map.size())
+    {
+        for (auto it = available_columns.begin(); it != available_columns.end(); ++it)
+        {
+            if (!names_in_block.count(it->name))
+                throw Exception("Expected column " + it->name, ErrorCodes::NOT_FOUND_COLUMN_IN_BLOCK);
+        }
+    }
+}
+
+TableStructureReadLockHolder IStorage::lockStructureForShare(bool will_add_new_data, const String & query_id)
+{
+    TableStructureReadLockHolder result;
+    if (will_add_new_data)
+        result.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Read, query_id);
+    result.structure_lock = structure_lock->getLock(RWLockImpl::Read, query_id);
+
+    if (is_dropped)
+        throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
+    return result;
+}
+
+TableStructureWriteLockHolder IStorage::lockAlterIntention(const String & query_id)
+{
+    TableStructureWriteLockHolder result;
+    result.alter_intention_lock = alter_intention_lock->getLock(RWLockImpl::Write, query_id);
+
+    if (is_dropped)
+        throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
+    return result;
+}
+
+void IStorage::lockNewDataStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id)
+{
+    if (!lock_holder.alter_intention_lock)
+        throw Exception("Alter intention lock for table " + getTableName() + " was not taken. This is a bug.", ErrorCodes::LOGICAL_ERROR);
+
+    lock_holder.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
+}
+
+void IStorage::lockStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id)
+{
+    if (!lock_holder.alter_intention_lock)
+        throw Exception("Alter intention lock for table " + getTableName() + " was not taken. This is a bug.", ErrorCodes::LOGICAL_ERROR);
+
+    if (!lock_holder.new_data_structure_lock)
+        lock_holder.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
+    lock_holder.structure_lock = structure_lock->getLock(RWLockImpl::Write, query_id);
+}
+
+TableStructureWriteLockHolder IStorage::lockExclusively(const String & query_id)
+{
+    TableStructureWriteLockHolder result;
+    result.alter_intention_lock = alter_intention_lock->getLock(RWLockImpl::Write, query_id);
+
+    if (is_dropped)
+        throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
+
+    result.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
+    result.structure_lock = structure_lock->getLock(RWLockImpl::Write, query_id);
+
+    return result;
+}
+
+void IStorage::alter(
+    const AlterCommands & params,
+    const String & database_name,
+    const String & table_name,
+    const Context & context,
+    TableStructureWriteLockHolder & table_lock_holder)
 {
     for (const auto & param : params)
     {

dbms/src/Storages/IStorage.h

@@ -1,18 +1,19 @@
 #pragma once
 
-#include <Common/Exception.h>
-#include <Common/RWLock.h>
 #include <Core/Names.h>
 #include <Core/QueryProcessingStage.h>
+#include <DataStreams/IBlockStream_fwd.h>
 #include <Databases/IDatabase.h>
-#include <Storages/ITableDeclaration.h>
-#include <Storages/TableStructureLockHolder.h>
-#include <Storages/SelectQueryInfo.h>
 #include <Interpreters/CancellationCode.h>
-#include <shared_mutex>
-#include <memory>
-#include <optional>
+#include <Storages/IStorage_fwd.h>
+#include <Storages/SelectQueryInfo.h>
+#include <Storages/TableStructureLockHolder.h>
 #include <Common/ActionLock.h>
+#include <Common/Exception.h>
+#include <Common/RWLock.h>
+
+#include <optional>
+#include <shared_mutex>
 
 
 namespace DB
@@ -25,22 +26,11 @@ namespace ErrorCodes
 }
 
 class Context;
-class IBlockInputStream;
-class IBlockOutputStream;
 
 using StorageActionBlockType = size_t;
 
-using BlockOutputStreamPtr = std::shared_ptr<IBlockOutputStream>;
-using BlockInputStreamPtr = std::shared_ptr<IBlockInputStream>;
-using BlockInputStreams = std::vector<BlockInputStreamPtr>;
-
 class ASTCreateQuery;
 
-class IStorage;
-
-using StoragePtr = std::shared_ptr<IStorage>;
-using StorageWeakPtr = std::weak_ptr<IStorage>;
-
 struct Settings;
 
 class AlterCommands;
@@ -48,108 +38,105 @@ class MutationCommands;
 class PartitionCommands;
 
 
-/** Storage. Responsible for
+/** Storage. Describes the table. Responsible for
   * - storage of the table data;
   * - the definition in which files (or not in files) the data is stored;
   * - data lookups and appends;
   * - data storage structure (compression, etc.)
   * - concurrent access to data (locks, etc.)
   */
-class IStorage : public std::enable_shared_from_this<IStorage>, private boost::noncopyable, public ITableDeclaration
+class IStorage : public std::enable_shared_from_this<IStorage>
 {
 public:
+    IStorage() = default;
+    explicit IStorage(ColumnsDescription columns_);
+
+    virtual ~IStorage() = default;
+    IStorage(const IStorage &) = delete;
+    IStorage & operator=(const IStorage &) = delete;
+
     /// The main name of the table type (for example, StorageMergeTree).
     virtual std::string getName() const = 0;
 
     /// The name of the table.
     virtual std::string getTableName() const = 0;
-    virtual std::string getDatabaseName() const { return {}; }  // FIXME: should be abstract method.
+    virtual std::string getDatabaseName() const { return {}; }  // FIXME: should be an abstract method!
 
-    /** Returns true if the storage receives data from a remote server or servers. */
+    /// Returns true if the storage receives data from a remote server or servers.
     virtual bool isRemote() const { return false; }
 
-    /** Returns true if the storage supports queries with the SAMPLE section. */
+    /// Returns true if the storage supports queries with the SAMPLE section.
     virtual bool supportsSampling() const { return false; }
 
-    /** Returns true if the storage supports queries with the FINAL section. */
+    /// Returns true if the storage supports queries with the FINAL section.
     virtual bool supportsFinal() const { return false; }
 
-    /** Returns true if the storage supports queries with the PREWHERE section. */
+    /// Returns true if the storage supports queries with the PREWHERE section.
     virtual bool supportsPrewhere() const { return false; }
 
-    /** Returns true if the storage replicates SELECT, INSERT and ALTER commands among replicas. */
+    /// Returns true if the storage replicates SELECT, INSERT and ALTER commands among replicas.
     virtual bool supportsReplication() const { return false; }
 
-    /** Returns true if the storage supports deduplication of inserted data blocks . */
+    /// Returns true if the storage supports deduplication of inserted data blocks.
     virtual bool supportsDeduplication() const { return false; }
 
 
+public: /// thread-unsafe part. lockStructure must be acquired
+    const ColumnsDescription & getColumns() const;
+    void setColumns(ColumnsDescription columns_);
+
+    const IndicesDescription & getIndices() const;
+    void setIndices(IndicesDescription indices_);
+
+    /// NOTE: these methods should include virtual columns,
+    ///       but should NOT include ALIAS columns (they are treated separately).
+    virtual NameAndTypePair getColumn(const String & column_name) const;
+    virtual bool hasColumn(const String & column_name) const;
+
+    Block getSampleBlock() const;
+    Block getSampleBlockNonMaterialized() const;
+    Block getSampleBlockForColumns(const Names & column_names) const; /// including virtual and alias columns.
+
+    /// Verify that all the requested names are in the table and are set correctly:
+    /// list of names is not empty and the names do not repeat.
+    void check(const Names & column_names) const;
+
+    /// Check that all the requested names are in the table and have the correct types.
+    void check(const NamesAndTypesList & columns) const;
+
+    /// Check that all names from the intersection of `names` and `columns` are in the table and have the same types.
+    void check(const NamesAndTypesList & columns, const Names & column_names) const;
+
+    /// Check that the data block contains all the columns of the table with the correct types,
+    /// contains only the columns of the table, and all the columns are different.
+    /// If |need_all| is set, then checks that all the columns of the table are in the block.
+    void check(const Block & block, bool need_all = false) const;
+
+private:
+    ColumnsDescription columns;
+    IndicesDescription indices;
+
+public:
     /// Acquire this lock if you need the table structure to remain constant during the execution of
     /// the query. If will_add_new_data is true, this means that the query will add new data to the table
     /// (INSERT or a parts merge).
-    TableStructureReadLockHolder lockStructureForShare(bool will_add_new_data, const String & query_id)
-    {
-        TableStructureReadLockHolder result;
-        if (will_add_new_data)
-            result.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Read, query_id);
-        result.structure_lock = structure_lock->getLock(RWLockImpl::Read, query_id);
-
-        if (is_dropped)
-            throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
-        return result;
-    }
+    TableStructureReadLockHolder lockStructureForShare(bool will_add_new_data, const String & query_id);
 
     /// Acquire this lock at the start of ALTER to lock out other ALTERs and make sure that only you
     /// can modify the table structure. It can later be upgraded to the exclusive lock.
-    TableStructureWriteLockHolder lockAlterIntention(const String & query_id)
-    {
-        TableStructureWriteLockHolder result;
-        result.alter_intention_lock = alter_intention_lock->getLock(RWLockImpl::Write, query_id);
-
-        if (is_dropped)
-            throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
-        return result;
-    }
+    TableStructureWriteLockHolder lockAlterIntention(const String & query_id);
 
     /// Upgrade alter intention lock and make sure that no new data is inserted into the table.
     /// This is used by the ALTER MODIFY of the MergeTree storage to consistently determine
     /// the set of parts that needs to be altered.
-    void lockNewDataStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id)
-    {
-        if (!lock_holder.alter_intention_lock)
-            throw Exception("Alter intention lock for table " + getTableName() + " was not taken. This is a bug.",
-                ErrorCodes::LOGICAL_ERROR);
-
-        lock_holder.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
-    }
+    void lockNewDataStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id);
 
     /// Upgrade alter intention lock to the full exclusive structure lock. This is done by ALTER queries
     /// to ensure that no other query uses the table structure and it can be safely changed.
-    void lockStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id)
-    {
-        if (!lock_holder.alter_intention_lock)
-            throw Exception("Alter intention lock for table " + getTableName() + " was not taken. This is a bug.",
-                ErrorCodes::LOGICAL_ERROR);
-
-        if (!lock_holder.new_data_structure_lock)
-            lock_holder.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
-        lock_holder.structure_lock = structure_lock->getLock(RWLockImpl::Write, query_id);
-    }
+    void lockStructureExclusively(TableStructureWriteLockHolder & lock_holder, const String & query_id);
 
     /// Acquire the full exclusive lock immediately. No other queries can run concurrently.
-    TableStructureWriteLockHolder lockExclusively(const String & query_id)
-    {
-        TableStructureWriteLockHolder result;
-        result.alter_intention_lock = alter_intention_lock->getLock(RWLockImpl::Write, query_id);
-
-        if (is_dropped)
-            throw Exception("Table is dropped", ErrorCodes::TABLE_IS_DROPPED);
-
-        result.new_data_structure_lock = new_data_structure_lock->getLock(RWLockImpl::Write, query_id);
-        result.structure_lock = structure_lock->getLock(RWLockImpl::Write, query_id);
-
-        return result;
-    }
+    TableStructureWriteLockHolder lockExclusively(const String & query_id);
 
     /** Returns stage to which query is going to be processed in read() function.
       * (Normally, the function only reads the columns from the list, but in other cases,
@@ -335,8 +322,11 @@ public:
     /// Returns additional columns that need to be read for FINAL to work.
     virtual Names getColumnsRequiredForFinal() const { return {}; }
 
-    using ITableDeclaration::ITableDeclaration;
-    using std::enable_shared_from_this<IStorage>::shared_from_this;
+protected:
+    /// Returns whether the column is virtual - by default all columns are real.
+    /// Initially reserved virtual column name may be shadowed by real column.
+    /// Returns false even for non-existent non-virtual columns.
+    virtual bool isVirtualColumn(const String & /* column_name */) const { return false; }
 
 private:
     /// You always need to take the next three locks in this order.
@@ -357,7 +347,4 @@ private:
     mutable RWLock structure_lock = RWLockImpl::create();
 };
 
-/// table name -> table
-using Tables = std::map<String, StoragePtr>;
-
 }

dbms/src/Storages/IStorage_fwd.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <Core/Types.h>
+
+#include <map>
+#include <memory>
+
+namespace DB
+{
+
+class IStorage;
+
+using StoragePtr = std::shared_ptr<IStorage>;
+using StorageWeakPtr = std::weak_ptr<IStorage>;
+using Tables = std::map<String, StoragePtr>;
+
+}

dbms/src/Storages/ITableDeclaration.cpp

@@ -1,290 +0,0 @@
-#include <Storages/ITableDeclaration.h>
-#include <Common/Exception.h>
-
-#include <boost/range/join.hpp>
-#include <sparsehash/dense_hash_map>
-#include <sparsehash/dense_hash_set>
-
-#include <unordered_set>
-#include <sstream>
-
-
-namespace DB
-{
-
-namespace ErrorCodes
-{
-    extern const int NO_SUCH_COLUMN_IN_TABLE;
-    extern const int EMPTY_LIST_OF_COLUMNS_QUERIED;
-    extern const int COLUMN_QUERIED_MORE_THAN_ONCE;
-    extern const int TYPE_MISMATCH;
-    extern const int DUPLICATE_COLUMN;
-    extern const int NOT_FOUND_COLUMN_IN_BLOCK;
-    extern const int EMPTY_LIST_OF_COLUMNS_PASSED;
-}
-
-const ColumnsDescription & ITableDeclaration::getColumns() const
-{
-    return columns;
-}
-
-const IndicesDescription & ITableDeclaration::getIndices() const
-{
-    return indices;
-}
-
-
-void ITableDeclaration::setColumns(ColumnsDescription columns_)
-{
-    if (columns_.getOrdinary().empty())
-        throw Exception("Empty list of columns passed", ErrorCodes::EMPTY_LIST_OF_COLUMNS_PASSED);
-    columns = std::move(columns_);
-}
-
-void ITableDeclaration::setIndices(IndicesDescription indices_)
-{
-    indices = std::move(indices_);
-}
-
-void ITableDeclaration::setConstraints(ConstraintsDescription constraints_)
-{
-    constraints = std::move(constraints_);
-}
-
-
-bool ITableDeclaration::hasColumn(const String & column_name) const
-{
-    return getColumns().hasPhysical(column_name); /// By default, we assume that there are no virtual columns in the storage.
-}
-
-NameAndTypePair ITableDeclaration::getColumn(const String & column_name) const
-{
-    return getColumns().getPhysical(column_name); /// By default, we assume that there are no virtual columns in the storage.
-}
-
-
-Block ITableDeclaration::getSampleBlock() const
-{
-    Block res;
-
-    for (const auto & col : getColumns().getAllPhysical())
-        res.insert({ col.type->createColumn(), col.type, col.name });
-
-    return res;
-}
-
-
-Block ITableDeclaration::getSampleBlockNonMaterialized() const
-{
-    Block res;
-
-    for (const auto & col : getColumns().getOrdinary())
-        res.insert({ col.type->createColumn(), col.type, col.name });
-
-    return res;
-}
-
-
-Block ITableDeclaration::getSampleBlockForColumns(const Names & column_names) const
-{
-    Block res;
-
-    NamesAndTypesList all_columns = getColumns().getAll();
-    std::unordered_map<String, DataTypePtr> columns_map;
-    for (const auto & elem : all_columns)
-        columns_map.emplace(elem.name, elem.type);
-
-    for (const auto & name : column_names)
-    {
-        auto it = columns_map.find(name);
-        if (it != columns_map.end())
-        {
-            res.insert({ it->second->createColumn(), it->second, it->first });
-        }
-        else
-        {
-            /// Virtual columns.
-            NameAndTypePair elem = getColumn(name);
-            res.insert({ elem.type->createColumn(), elem.type, elem.name });
-        }
-    }
-
-    return res;
-}
-
-
-static std::string listOfColumns(const NamesAndTypesList & available_columns)
-{
-    std::stringstream s;
-    for (auto it = available_columns.begin(); it != available_columns.end(); ++it)
-    {
-        if (it != available_columns.begin())
-            s << ", ";
-        s << it->name;
-    }
-    return s.str();
-}
-
-
-using NamesAndTypesMap = GOOGLE_NAMESPACE::dense_hash_map<StringRef, const IDataType *, StringRefHash>;
-
-static NamesAndTypesMap & getColumnsMapImpl(NamesAndTypesMap & res) { return res; }
-
-template <typename Arg, typename... Args>
-static NamesAndTypesMap & getColumnsMapImpl(NamesAndTypesMap & res, const Arg & arg, const Args &... args)
-{
-    static_assert(std::is_same_v<Arg, NamesAndTypesList>, "getColumnsMap requires arguments of type NamesAndTypesList");
-
-    for (const auto & column : arg)
-        res.insert({column.name, column.type.get()});
-
-    return getColumnsMapImpl(res, args...);
-}
-
-template <typename... Args>
-static NamesAndTypesMap getColumnsMap(const Args &... args)
-{
-    NamesAndTypesMap res;
-    res.set_empty_key(StringRef());
-
-    return getColumnsMapImpl(res, args...);
-}
-
-
-void ITableDeclaration::check(const Names & column_names) const
-{
-    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
-
-    if (column_names.empty())
-        throw Exception("Empty list of columns queried. There are columns: " + listOfColumns(available_columns),
-            ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED);
-
-    const auto columns_map = getColumnsMap(available_columns);
-
-    using UniqueStrings = GOOGLE_NAMESPACE::dense_hash_set<StringRef, StringRefHash>;
-    UniqueStrings unique_names;
-    unique_names.set_empty_key(StringRef());
-
-    for (const auto & name : column_names)
-    {
-        if (columns_map.end() == columns_map.find(name))
-            throw Exception("There is no column with name " + name + " in table. There are columns: " + listOfColumns(available_columns),
-                ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
-
-        if (unique_names.end() != unique_names.find(name))
-            throw Exception("Column " + name + " queried more than once",
-                ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
-        unique_names.insert(name);
-    }
-}
-
-
-void ITableDeclaration::check(const NamesAndTypesList & provided_columns) const
-{
-    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
-    const auto columns_map = getColumnsMap(available_columns);
-
-    using UniqueStrings = GOOGLE_NAMESPACE::dense_hash_set<StringRef, StringRefHash>;
-    UniqueStrings unique_names;
-    unique_names.set_empty_key(StringRef());
-
-    for (const NameAndTypePair & column : provided_columns)
-    {
-        NamesAndTypesMap::const_iterator it = columns_map.find(column.name);
-        if (columns_map.end() == it)
-            throw Exception("There is no column with name " + column.name + ". There are columns: "
-                + listOfColumns(available_columns), ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
-
-        if (!column.type->equals(*it->second))
-            throw Exception("Type mismatch for column " + column.name + ". Column has type "
-                + it->second->getName() + ", got type " + column.type->getName(), ErrorCodes::TYPE_MISMATCH);
-
-        if (unique_names.end() != unique_names.find(column.name))
-            throw Exception("Column " + column.name + " queried more than once",
-                ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
-        unique_names.insert(column.name);
-    }
-}
-
-
-void ITableDeclaration::check(const NamesAndTypesList & provided_columns, const Names & column_names) const
-{
-    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
-    const auto available_columns_map = getColumnsMap(available_columns);
-    const NamesAndTypesMap & provided_columns_map = getColumnsMap(provided_columns);
-
-    if (column_names.empty())
-        throw Exception("Empty list of columns queried. There are columns: " + listOfColumns(available_columns),
-            ErrorCodes::EMPTY_LIST_OF_COLUMNS_QUERIED);
-
-    using UniqueStrings = GOOGLE_NAMESPACE::dense_hash_set<StringRef, StringRefHash>;
-    UniqueStrings unique_names;
-    unique_names.set_empty_key(StringRef());
-
-    for (const String & name : column_names)
-    {
-        NamesAndTypesMap::const_iterator it = provided_columns_map.find(name);
-        if (provided_columns_map.end() == it)
-            continue;
-
-        NamesAndTypesMap::const_iterator jt = available_columns_map.find(name);
-        if (available_columns_map.end() == jt)
-            throw Exception("There is no column with name " + name + ". There are columns: "
-                + listOfColumns(available_columns), ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
-
-        if (!it->second->equals(*jt->second))
-            throw Exception("Type mismatch for column " + name + ". Column has type "
-                + jt->second->getName() + ", got type " + it->second->getName(), ErrorCodes::TYPE_MISMATCH);
-
-        if (unique_names.end() != unique_names.find(name))
-            throw Exception("Column " + name + " queried more than once",
-                ErrorCodes::COLUMN_QUERIED_MORE_THAN_ONCE);
-        unique_names.insert(name);
-    }
-}
-
-
-void ITableDeclaration::check(const Block & block, bool need_all) const
-{
-    const NamesAndTypesList & available_columns = getColumns().getAllPhysical();
-    const auto columns_map = getColumnsMap(available_columns);
-
-    NameSet names_in_block;
-
-    block.checkNumberOfRows();
-
-    for (const auto & column : block)
-    {
-        if (names_in_block.count(column.name))
-            throw Exception("Duplicate column " + column.name + " in block",
-                            ErrorCodes::DUPLICATE_COLUMN);
-
-        names_in_block.insert(column.name);
-
-        NamesAndTypesMap::const_iterator it = columns_map.find(column.name);
-        if (columns_map.end() == it)
-            throw Exception("There is no column with name " + column.name + ". There are columns: "
-                + listOfColumns(available_columns), ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
-
-        if (!column.type->equals(*it->second))
-            throw Exception("Type mismatch for column " + column.name + ". Column has type "
-                + it->second->getName() + ", got type " + column.type->getName(), ErrorCodes::TYPE_MISMATCH);
-    }
-
-    if (need_all && names_in_block.size() < columns_map.size())
-    {
-        for (NamesAndTypesList::const_iterator it = available_columns.begin(); it != available_columns.end(); ++it)
-        {
-            if (!names_in_block.count(it->name))
-                throw Exception("Expected column " + it->name, ErrorCodes::NOT_FOUND_COLUMN_IN_BLOCK);
-        }
-    }
-}
-
-
-ITableDeclaration::ITableDeclaration(ColumnsDescription columns_)
-{
-    setColumns(std::move(columns_));
-}
-
-}

dbms/src/Storages/ITableDeclaration.h

@@ -1,67 +0,0 @@
-#pragma once
-
-#include <Storages/ColumnsDescription.h>
-#include <Storages/IndicesDescription.h>
-#include <Storages/ConstraintsDescription.h>
-
-
-namespace DB
-{
-
-/** Description of the table.
-  * Is not thread safe. See IStorage::lockStructure ().
-  */
-class ITableDeclaration
-{
-public:
-    const ColumnsDescription & getColumns() const;
-    void setColumns(ColumnsDescription columns_);
-
-    const IndicesDescription & getIndices() const;
-    void setIndices(IndicesDescription indices_);
-
-    virtual const ConstraintsDescription & getConstraints() const { return constraints; }
-    virtual void setConstraints(ConstraintsDescription constraints_);
-
-    /// NOTE: These methods should include virtual columns, but should NOT include ALIAS columns
-    /// (they are treated separately).
-    virtual NameAndTypePair getColumn(const String & column_name) const;
-    virtual bool hasColumn(const String & column_name) const;
-
-    Block getSampleBlock() const;
-    Block getSampleBlockNonMaterialized() const;
-
-    /// Including virtual and alias columns.
-    Block getSampleBlockForColumns(const Names & column_names) const;
-
-    /** Verify that all the requested names are in the table and are set correctly.
-      * (the list of names is not empty and the names do not repeat)
-      */
-    void check(const Names & column_names) const;
-
-    /** Check that all the requested names are in the table and have the correct types.
-      */
-    void check(const NamesAndTypesList & columns) const;
-
-    /** Check that all names from the intersection of `names` and `columns` are in the table and have the same types.
-      */
-    void check(const NamesAndTypesList & columns, const Names & column_names) const;
-
-    /** Check that the data block contains all the columns of the table with the correct types,
-      *  contains only the columns of the table, and all the columns are different.
-      * If need_all, checks that all the columns of the table are in the block.
-      */
-    void check(const Block & block, bool need_all = false) const;
-
-
-    ITableDeclaration() = default;
-    explicit ITableDeclaration(ColumnsDescription columns_);
-    virtual ~ITableDeclaration() = default;
-
-private:
-    ColumnsDescription columns;
-    IndicesDescription indices;
-    ConstraintsDescription constraints;
-};
-
-}

dbms/src/Storages/Kafka/KafkaSettings.h

@@ -23,7 +23,8 @@ struct KafkaSettings : public SettingsCollection<KafkaSettings>
     M(SettingString, kafka_schema, "", "Schema identifier (used by schema-based formats) for Kafka engine") \
     M(SettingUInt64, kafka_num_consumers, 1, "The number of consumers per table for Kafka engine.") \
     M(SettingUInt64, kafka_max_block_size, 0, "The maximum block size per table for Kafka engine.") \
-    M(SettingUInt64, kafka_skip_broken_messages, 0, "Skip at least this number of broken messages from Kafka topic per block")
+    M(SettingUInt64, kafka_skip_broken_messages, 0, "Skip at least this number of broken messages from Kafka topic per block") \
+    M(SettingUInt64, kafka_commit_every_batch, 1, "Commit every consumed and handled batch instead of a single commit after writing a whole block")
 
     DECLARE_SETTINGS_COLLECTION(LIST_OF_KAFKA_SETTINGS)
 

dbms/src/Storages/Kafka/ReadBufferFromKafkaConsumer.cpp

@@ -40,7 +40,7 @@ void ReadBufferFromKafkaConsumer::unsubscribe()
 /// Do commit messages implicitly after we processed the previous batch.
 bool ReadBufferFromKafkaConsumer::nextImpl()
 {
-    /// NOTE: ReadBuffer was implemented with a immutable buffer contents in mind.
+    /// NOTE: ReadBuffer was implemented with an immutable underlying contents in mind.
     ///       If we failed to poll any message once - don't try again.
     ///       Otherwise, the |poll_timeout| expectations get flawn.
     if (stalled)
@@ -48,7 +48,8 @@ bool ReadBufferFromKafkaConsumer::nextImpl()
 
     if (current == messages.end())
     {
-        commit();
+        if (intermediate_commit)
+            commit();
         messages = consumer->poll_batch(batch_size, std::chrono::milliseconds(poll_timeout));
         current = messages.begin();
 

dbms/src/Storages/Kafka/ReadBufferFromKafkaConsumer.h

@@ -15,12 +15,14 @@ using ConsumerPtr = std::shared_ptr<cppkafka::Consumer>;
 class ReadBufferFromKafkaConsumer : public ReadBuffer
 {
 public:
-    ReadBufferFromKafkaConsumer(ConsumerPtr consumer_, Poco::Logger * log_, size_t max_batch_size, size_t poll_timeout_)
+    ReadBufferFromKafkaConsumer(
+        ConsumerPtr consumer_, Poco::Logger * log_, size_t max_batch_size, size_t poll_timeout_, bool intermediate_commit_)
         : ReadBuffer(nullptr, 0)
         , consumer(consumer_)
         , log(log_)
         , batch_size(max_batch_size)
         , poll_timeout(poll_timeout_)
+        , intermediate_commit(intermediate_commit_)
         , current(messages.begin())
     {
     }
@@ -39,6 +41,7 @@ private:
     const size_t batch_size = 1;
     const size_t poll_timeout = 0;
     bool stalled = false;
+    bool intermediate_commit = true;
 
     Messages messages;
     Messages::const_iterator current;

dbms/src/Storages/Kafka/StorageKafka.cpp

@@ -71,7 +71,8 @@ StorageKafka::StorageKafka(
     const ColumnsDescription & columns_,
     const String & brokers_, const String & group_, const Names & topics_,
     const String & format_name_, char row_delimiter_, const String & schema_name_,
-    size_t num_consumers_, UInt64 max_block_size_, size_t skip_broken_)
+    size_t num_consumers_, UInt64 max_block_size_, size_t skip_broken_,
+    bool intermediate_commit_)
     : IStorage{columns_},
     table_name(table_name_), database_name(database_name_), global_context(context_),
     topics(global_context.getMacros()->expand(topics_)),
@@ -82,7 +83,7 @@ StorageKafka::StorageKafka(
     schema_name(global_context.getMacros()->expand(schema_name_)),
     num_consumers(num_consumers_), max_block_size(max_block_size_), log(&Logger::get("StorageKafka (" + table_name_ + ")")),
     semaphore(0, num_consumers_),
-    skip_broken(skip_broken_)
+    skip_broken(skip_broken_), intermediate_commit(intermediate_commit_)
 {
     task = global_context.getSchedulePool().createTask(log->name(), [this]{ streamThread(); });
     task->deactivate();
@@ -212,7 +213,8 @@ BufferPtr StorageKafka::createBuffer()
         batch_size = settings.max_block_size.value;
     size_t poll_timeout = settings.stream_poll_timeout_ms.totalMilliseconds();
 
-    return std::make_shared<DelimitedReadBuffer>(std::make_unique<ReadBufferFromKafkaConsumer>(consumer, log, batch_size, poll_timeout), row_delimiter);
+    return std::make_shared<DelimitedReadBuffer>(
+        std::make_unique<ReadBufferFromKafkaConsumer>(consumer, log, batch_size, poll_timeout, intermediate_commit), row_delimiter);
 }
 
 BufferPtr StorageKafka::claimBuffer()
@@ -380,6 +382,7 @@ void registerStorageKafka(StorageFactory & factory)
           * - Number of consumers
           * - Max block size for background consumption
           * - Skip (at least) unreadable messages number
+          * - Do intermediate commits when the batch consumed and handled
           */
 
         // Check arguments and settings
@@ -414,6 +417,8 @@ void registerStorageKafka(StorageFactory & factory)
         CHECK_KAFKA_STORAGE_ARGUMENT(7, kafka_num_consumers)
         CHECK_KAFKA_STORAGE_ARGUMENT(8, kafka_max_block_size)
         CHECK_KAFKA_STORAGE_ARGUMENT(9, kafka_skip_broken_messages)
+        CHECK_KAFKA_STORAGE_ARGUMENT(10, kafka_commit_every_batch)
+
         #undef CHECK_KAFKA_STORAGE_ARGUMENT
 
         // Get and check broker list
@@ -598,9 +603,27 @@ void registerStorageKafka(StorageFactory & factory)
             skip_broken = static_cast<size_t>(kafka_settings.kafka_skip_broken_messages.value);
         }
 
+        bool intermediate_commit = true;
+        if (args_count >= 10)
+        {
+            const auto * ast = engine_args[9]->as<ASTLiteral>();
+            if (ast && ast->value.getType() == Field::Types::UInt64)
+            {
+                intermediate_commit = static_cast<bool>(safeGet<UInt64>(ast->value));
+            }
+            else
+            {
+                throw Exception("Flag for committing every batch must be 0 or 1", ErrorCodes::BAD_ARGUMENTS);
+            }
+        }
+        else if (kafka_settings.kafka_commit_every_batch.changed)
+        {
+            intermediate_commit = static_cast<bool>(kafka_settings.kafka_commit_every_batch);
+        }
+
         return StorageKafka::create(
             args.table_name, args.database_name, args.context, args.columns,
-            brokers, group, topics, format, row_delimiter, schema, num_consumers, max_block_size, skip_broken);
+            brokers, group, topics, format, row_delimiter, schema, num_consumers, max_block_size, skip_broken, intermediate_commit);
     });
 }
 

dbms/src/Storages/Kafka/StorageKafka.h

@@ -77,6 +77,8 @@ private:
 
     size_t skip_broken;
 
+    bool intermediate_commit;
+
     // Stream thread
     BackgroundSchedulePool::TaskHolder task;
     std::atomic<bool> stream_cancelled{false};
@@ -99,7 +101,8 @@ protected:
         const ColumnsDescription & columns_,
         const String & brokers_, const String & group_, const Names & topics_,
         const String & format_name_, char row_delimiter_, const String & schema_name_,
-        size_t num_consumers_, UInt64 max_block_size_, size_t skip_broken);
+        size_t num_consumers_, UInt64 max_block_size_, size_t skip_broken,
+        bool intermediate_commit_);
 };
 
 }

dbms/src/Storages/MergeTree/DataPartsExchange.h

@@ -2,7 +2,7 @@
 
 #include <Interpreters/InterserverIOHandler.h>
 #include <Storages/MergeTree/MergeTreeData.h>
-#include <Storages/IStorage.h>
+#include <Storages/IStorage_fwd.h>
 #include <IO/HashingWriteBuffer.h>
 #include <IO/copyData.h>
 #include <IO/ConnectionTimeouts.h>

dbms/src/Storages/MutationCommands.h

@@ -1,6 +1,8 @@
 #pragma once
 
 #include <Parsers/ASTAlterQuery.h>
+#include <Storages/IStorage_fwd.h>
+
 #include <optional>
 #include <unordered_map>
 
@@ -8,7 +10,6 @@
 namespace DB
 {
 
-class IStorage;
 class Context;
 class WriteBuffer;
 class ReadBuffer;

dbms/src/Storages/PartitionCommands.h

@@ -1,16 +1,17 @@
 #pragma once
 
-#include <Core/Types.h>
 #include <Core/Field.h>
+#include <Core/Types.h>
 #include <Parsers/IAST.h>
-#include <vector>
+#include <Storages/IStorage_fwd.h>
+
 #include <optional>
+#include <vector>
 
 
 namespace DB
 {
 
-class IStorage;
 class ASTAlterCommand;
 
 struct PartitionCommand

dbms/src/Storages/StorageFactory.h

@@ -1,7 +1,9 @@
 #pragma once
 
 #include <Common/NamePrompter.h>
-#include <Storages/IStorage.h>
+#include <Parsers/IAST_fwd.h>
+#include <Storages/ColumnsDescription.h>
+#include <Storages/IStorage_fwd.h>
 #include <ext/singleton.h>
 #include <unordered_map>
 

dbms/src/Storages/StorageMaterializedView.cpp

@@ -11,6 +11,8 @@
 #include <Interpreters/InterpreterRenameQuery.h>
 #include <Interpreters/DatabaseAndTableWithAlias.h>
 #include <Interpreters/AddDefaultDatabaseVisitor.h>
+#include <DataStreams/IBlockInputStream.h>
+#include <DataStreams/IBlockOutputStream.h>
 
 #include <Storages/StorageFactory.h>
 

dbms/src/Storages/StorageMerge.cpp

@@ -57,18 +57,26 @@ StorageMerge::StorageMerge(
 }
 
 
-/// NOTE Structure of underlying tables as well as their set are not constant,
-///  so the results of these methods may become obsolete after the call.
+/// NOTE: structure of underlying tables as well as their set are not constant,
+///       so the results of these methods may become obsolete after the call.
+
+bool StorageMerge::isVirtualColumn(const String & column_name) const
+{
+    if (column_name != "_table")
+        return false;
+
+    return !IStorage::hasColumn(column_name);
+}
 
 NameAndTypePair StorageMerge::getColumn(const String & column_name) const
 {
+    if (IStorage::hasColumn(column_name))
+        return IStorage::getColumn(column_name);
+
     /// virtual column of the Merge table itself
     if (column_name == "_table")
         return { column_name, std::make_shared<DataTypeString>() };
 
-    if (IStorage::hasColumn(column_name))
-        return IStorage::getColumn(column_name);
-
     /// virtual (and real) columns of the underlying tables
     auto first_table = getFirstTable([](auto &&) { return true; });
     if (first_table)
@@ -188,7 +196,7 @@ BlockInputStreams StorageMerge::read(
 
     for (const auto & column_name : column_names)
     {
-        if (column_name == "_table")
+        if (isVirtualColumn(column_name))
             has_table_virtual_column = true;
         else
             real_column_names.push_back(column_name);

dbms/src/Storages/StorageMerge.h

@@ -84,6 +84,8 @@ protected:
 
     void convertingSourceStream(const Block & header, const Context & context, ASTPtr & query,
                                 BlockInputStreamPtr & source_stream, QueryProcessingStage::Enum processed_stage);
+
+    bool isVirtualColumn(const String & column_name) const override;
 };
 
 }

dbms/src/Storages/System/StorageSystemPartsBase.cpp

@@ -259,7 +259,7 @@ NameAndTypePair StorageSystemPartsBase::getColumn(const String & column_name) co
     if (column_name == "_state")
         return NameAndTypePair("_state", std::make_shared<DataTypeString>());
 
-    return ITableDeclaration::getColumn(column_name);
+    return IStorage::getColumn(column_name);
 }
 
 bool StorageSystemPartsBase::hasColumn(const String & column_name) const
@@ -267,7 +267,7 @@ bool StorageSystemPartsBase::hasColumn(const String & column_name) const
     if (column_name == "_state")
         return true;
 
-    return ITableDeclaration::hasColumn(column_name);
+    return IStorage::hasColumn(column_name);
 }
 
 StorageSystemPartsBase::StorageSystemPartsBase(std::string name_, NamesAndTypesList && columns_)

dbms/src/Storages/System/StorageSystemPartsColumns.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <ext/shared_ptr_helper.h>
-#include <Storages/IStorage.h>
 #include <Storages/System/StorageSystemPartsBase.h>
 
 

dbms/src/Storages/tests/gtest_transform_query_for_external_database.cpp

@@ -0,0 +1,75 @@
+#pragma GCC diagnostic ignored "-Wsign-compare"
+#ifdef __clang__
+    #pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
+    #pragma clang diagnostic ignored "-Wundef"
+#endif
+#include <gtest/gtest.h>
+
+#include <Storages/transformQueryForExternalDatabase.h>
+#include <Parsers/ParserSelectQuery.h>
+#include <Parsers/parseQuery.h>
+#include <DataTypes/DataTypesNumber.h>
+#include <Interpreters/Context.h>
+#include <Databases/DatabaseMemory.h>
+#include <Storages/StorageMemory.h>
+#include <Functions/registerFunctions.h>
+
+
+using namespace DB;
+
+
+/// NOTE How to do better?
+struct State
+{
+    Context context{Context::createGlobal()};
+    NamesAndTypesList columns{{"column", std::make_shared<DataTypeUInt8>()}};
+
+    State()
+    {
+        registerFunctions();
+        DatabasePtr database = std::make_shared<DatabaseMemory>("test");
+        database->attachTable("table", StorageMemory::create("table", ColumnsDescription{columns}));
+        context.addDatabase("test", database);
+        context.setCurrentDatabase("test");
+    }
+};
+
+State & state()
+{
+    static State res;
+    return res;
+}
+
+
+void check(const std::string & query, const std::string & expected, const Context & context, const NamesAndTypesList & columns)
+{
+    ParserSelectQuery parser;
+    ASTPtr ast = parseQuery(parser, query, 1000);
+    std::string transformed_query = transformQueryForExternalDatabase(*ast, columns, IdentifierQuotingStyle::DoubleQuotes, "test", "table", context);
+
+    EXPECT_EQ(transformed_query, expected);
+}
+
+
+TEST(TransformQueryForExternalDatabase, InWithSingleElement)
+{
+    check("SELECT column FROM test.table WHERE 1 IN (1)",
+          "SELECT \"column\" FROM \"test\".\"table\"  WHERE 1 IN (1)",
+          state().context, state().columns);
+    check("SELECT column FROM test.table WHERE column IN (1, 2)",
+          "SELECT \"column\" FROM \"test\".\"table\"  WHERE \"column\" IN (1, 2)",
+          state().context, state().columns);
+    check("SELECT column FROM test.table WHERE column NOT IN ('hello', 'world')",
+          "SELECT \"column\" FROM \"test\".\"table\"  WHERE \"column\" NOT IN ('hello', 'world')",
+          state().context, state().columns);
+}
+
+TEST(TransformQueryForExternalDatabase, Like)
+{
+    check("SELECT column FROM test.table WHERE column LIKE '%hello%'",
+          "SELECT \"column\" FROM \"test\".\"table\"  WHERE \"column\" LIKE '%hello%'",
+          state().context, state().columns);
+    check("SELECT column FROM test.table WHERE column NOT LIKE 'w%rld'",
+          "SELECT \"column\" FROM \"test\".\"table\"  WHERE \"column\" NOT LIKE 'w%rld'",
+          state().context, state().columns);
+}