Merge branch 'master' into zookeeper-add-extra-list-argument

base/base/defines.h

@@ -124,21 +124,37 @@
     #endif
 #endif
 
-// Macros for Clang Thread Safety Analysis (TSA). They can be safely ignored by other compilers.
+/// Macros for Clang Thread Safety Analysis (TSA). They can be safely ignored by other compilers.
-// Feel free to extend, but please stay close to https://clang.llvm.org/docs/ThreadSafetyAnalysis.html#mutexheader
+/// Feel free to extend, but please stay close to https://clang.llvm.org/docs/ThreadSafetyAnalysis.html#mutexheader
 #if defined(__clang__)
-#    define TSA_GUARDED_BY(...) __attribute__((guarded_by(__VA_ARGS__)))                       // data is protected by given capability
+#    define TSA_GUARDED_BY(...) __attribute__((guarded_by(__VA_ARGS__)))                       /// data is protected by given capability
-#    define TSA_PT_GUARDED_BY(...) __attribute__((pt_guarded_by(__VA_ARGS__)))                 // pointed-to data is protected by the given capability
+#    define TSA_PT_GUARDED_BY(...) __attribute__((pt_guarded_by(__VA_ARGS__)))                 /// pointed-to data is protected by the given capability
-#    define TSA_REQUIRES(...) __attribute__((requires_capability(__VA_ARGS__)))                // thread needs exclusive possession of given capability
+#    define TSA_REQUIRES(...) __attribute__((requires_capability(__VA_ARGS__)))                /// thread needs exclusive possession of given capability
-#    define TSA_REQUIRES_SHARED(...) __attribute__((requires_shared_capability(__VA_ARGS__)))  // thread needs shared possession of given capability
+#    define TSA_REQUIRES_SHARED(...) __attribute__((requires_shared_capability(__VA_ARGS__)))  /// thread needs shared possession of given capability
-#    define TSA_ACQUIRED_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))               // annotated lock must be locked after given lock
+#    define TSA_ACQUIRED_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))               /// annotated lock must be locked after given lock
-#    define TSA_NO_THREAD_SAFETY_ANALYSIS __attribute__((no_thread_safety_analysis))           // disable TSA for a function
+#    define TSA_NO_THREAD_SAFETY_ANALYSIS __attribute__((no_thread_safety_analysis))           /// disable TSA for a function
+
+/// Macros for suppressing TSA warnings for specific reads/writes (instead of suppressing it for the whole function)
+/// Consider adding a comment before using these macros.
+#   define TSA_SUPPRESS_WARNING_FOR_READ(x) [&]() TSA_NO_THREAD_SAFETY_ANALYSIS -> const auto & { return (x); }()
+#   define TSA_SUPPRESS_WARNING_FOR_WRITE(x) [&]() TSA_NO_THREAD_SAFETY_ANALYSIS -> auto & { return (x); }()
+
+/// This macro is useful when only one thread writes to a member
+/// and you want to read this member from the same thread without locking a mutex.
+/// It's safe (because no concurrent writes are possible), but TSA generates a warning.
+/// (Seems like there's no way to verify it, but it makes sense to distinguish it from TSA_SUPPRESS_WARNING_FOR_READ for readability)
+#   define TSA_READ_ONE_THREAD(x) TSA_SUPPRESS_WARNING_FOR_READ(x)
+
 #else
 #    define TSA_GUARDED_BY(...)
 #    define TSA_PT_GUARDED_BY(...)
 #    define TSA_REQUIRES(...)
 #    define TSA_REQUIRES_SHARED(...)
 #    define TSA_NO_THREAD_SAFETY_ANALYSIS
+
+#    define TSA_SUPPRESS_WARNING_FOR_READ(x)
+#    define TSA_SUPPRESS_WARNING_FOR_WRITE(x)
+#    define TSA_READ_ONE_THREAD(x)
 #endif
 
 /// A template function for suppressing warnings about unused variables or function results.

contrib/mariadb-connector-c

@@ -1 +1 @@
-Subproject commit 5f4034a3a6376416504f17186c55fe401c6d8e5e
+Subproject commit e39608998f5f6944ece9ec61f48e9172ec1de660

contrib/poco

@@ -1 +1 @@
-Subproject commit de35b9fd72b57127abdc3a5beaf0e320d767e356
+Subproject commit 0e32cb42db76ddaa76848470219056908053b676

contrib/poco-cmake/XML/CMakeLists.txt

@@ -11,6 +11,7 @@ add_library (_poco_xml_expat ${SRCS_EXPAT})
 add_library (Poco::XML::Expat ALIAS _poco_xml_expat)
 
 target_include_directories (_poco_xml_expat PUBLIC "${LIBRARY_DIR}/XML/include")
+target_include_directories (_poco_xml_expat PRIVATE "${LIBRARY_DIR}/Foundation/include")
 
 # Poco::XML
 

docker/test/performance-comparison/download.sh

@@ -73,6 +73,9 @@ function download
     ) &
 
     wait
+    echo "ATTACH DATABASE default ENGINE=Ordinary" > db0/metadata/default.sql
+    echo "ATTACH DATABASE datasets ENGINE=Ordinary" > db0/metadata/datasets.sql
+    ls db0/metadata
 }
 
 download

docker/test/stateful/run.sh

@@ -120,6 +120,10 @@ function run_tests()
         ADDITIONAL_OPTIONS+=('--replicated-database')
     fi
 
+    if [[ -n "$USE_DATABASE_ORDINARY" ]] && [[ "$USE_DATABASE_ORDINARY" -eq 1 ]]; then
+        ADDITIONAL_OPTIONS+=('--db-engine=Ordinary')
+    fi
+
     set +e
     clickhouse-test -j 2 --testname --shard --zookeeper --check-zookeeper-session --no-stateless --hung-check --print-time \
         --skip 00168_parallel_processing_on_replicas "${ADDITIONAL_OPTIONS[@]}" \

docker/test/stateless/run.sh

@@ -115,6 +115,10 @@ function run_tests()
         ADDITIONAL_OPTIONS+=("$RUN_BY_HASH_TOTAL")
     fi
 
+    if [[ -n "$USE_DATABASE_ORDINARY" ]] && [[ "$USE_DATABASE_ORDINARY" -eq 1 ]]; then
+        ADDITIONAL_OPTIONS+=('--db-engine=Ordinary')
+    fi
+
     set +e
     clickhouse-test --testname --shard --zookeeper --check-zookeeper-session --hung-check --print-time \
             --test-runs "$NUM_TRIES" "${ADDITIONAL_OPTIONS[@]}" 2>&1 \

docker/test/stress/run.sh

@@ -284,6 +284,11 @@ then
 
     rm -rf /var/lib/clickhouse/*
 
+    # Make BC check more funny by forcing Ordinary engine for system database
+    # New version will try to convert it to Atomic on startup
+    mkdir /var/lib/clickhouse/metadata
+    echo "ATTACH DATABASE system ENGINE=Ordinary" > /var/lib/clickhouse/metadata/system.sql
+
     # Install previous release packages
     install_packages previous_release_package_folder
 

docs/en/sql-reference/functions/geo/index.md

@@ -3,6 +3,74 @@ sidebar_label: Geo
 sidebar_position: 62
 ---
 
-# Geo Functions
+# Geo Functions 
+
+## Geographical Coordinates Functions
+
+-   [greatCircleDistance](./coordinates.md#greatCircleDistance)
+-   [geoDistance](./coordinates.md#geoDistance)
+-   [greatCircleAngle](./coordinates.md#greatCircleAngle)
+-   [pointInEllipses](./coordinates.md#pointInEllipses)
+-   [pointInPolygon](./coordinates.md#pointInPolygon)
+
+## Geohash Functions
+-   [geohashEncode](./geohash.md#geohashEncode)
+-   [geohashDecode](./geohash.md#geohashDecode)
+-   [geohashesInBox](./geohash.md#geohashesInBox)
+
+## H3 Indexes Functions
+
+-   [h3IsValid](./h3.md#h3IsValid)
+-   [h3GetResolution](./h3.md#h3GetResolution)
+-   [h3EdgeAngle](./h3.md#h3EdgeAngle)
+-   [h3EdgeLengthM​](./h3.md#h3EdgeLengthM​)
+-   [h3EdgeLengthKm](./h3.md#h3EdgeLengthKm)
+-   [geoToH3](./h3.md#geoToH3)
+-   [h3ToGeo](./h3.md#h3ToGeo)
+-   [h3ToGeoBoundary](./h3.md#h3ToGeoBoundary)
+-   [h3kRing](./h3.md#h3kRing)
+-   [h3GetBaseCell](./h3.md#h3GetBaseCell)
+-   [h3HexAreaM2](./h3.md#h3HexAreaM2)
+-   [h3HexAreaKm2](./h3.md#h3HexAreaKm2)
+-   [h3IndexesAreNeighbors](./h3.md#h3IndexesAreNeighbors)
+-   [h3ToChildren](./h3.md#h3ToChildren)
+-   [h3ToParent](./h3.md#h3ToParent)
+-   [h3ToString](./h3.md#h3ToString)
+-   [stringToH3](./h3.md#stringToH3)
+-   [h3GetResolution](./h3.md#h3GetResolution)
+-   [h3IsResClassIII](./h3.md#h3IsResClassIII)
+-   [h3IsPentagon](./h3.md#h3IsPentagon)
+-   [h3GetFaces](./h3.md#h3GetFaces)
+-   [h3CellAreaM2](./h3.md#h3CellAreaM2)
+-   [h3CellAreaRads2](./h3.md#h3CellAreaRads2)
+-   [h3ToCenterChild](./h3.md#h3ToCenterChild)
+-   [h3ExactEdgeLengthM](./h3.md#h3ExactEdgeLengthM)
+-   [h3ExactEdgeLengthKm](./h3.md#h3ExactEdgeLengthKm)
+-   [h3ExactEdgeLengthRads](./h3.md#h3ExactEdgeLengthRads)
+-   [h3NumHexagons](./h3.md#h3NumHexagons)
+-   [h3Line](./h3.md#h3Line)
+-   [h3Distance](./h3.md#h3Distance)
+-   [h3HexRing](./h3.md#h3HexRing)
+-   [h3GetUnidirectionalEdge](./h3.md#h3GetUnidirectionalEdge)
+-   [h3UnidirectionalEdgeIsValid](./h3.md#h3UnidirectionalEdgeIsValid)
+-   [h3GetOriginIndexFromUnidirectionalEdge](./h3.md#h3GetOriginIndexFromUnidirectionalEdge)
+-   [h3GetDestinationIndexFromUnidirectionalEdge](./h3.md#h3GetDestinationIndexFromUnidirectionalEdge)
+-   [h3GetIndexesFromUnidirectionalEdge](./h3.md#h3GetIndexesFromUnidirectionalEdge)
+-   [h3GetUnidirectionalEdgesFromHexagon](./h3.md#h3GetUnidirectionalEdgesFromHexagon)
+-   [h3GetUnidirectionalEdgeBoundary](./h3.md#h3GetUnidirectionalEdgeBoundary)
+
+## S2 Index Functions
+
+-   [geoToS2](./s2.md#geoToS2)
+-   [s2ToGeo](./s2.md#s2ToGeo)
+-   [s2GetNeighbors](./s2.md#s2GetNeighbors)
+-   [s2CellsIntersect](./s2.md#s2CellsIntersect)
+-   [s2CapContains](./s2.md#s2CapContains)
+-   [s2CapUnion](./s2.md#s2CapUnion)
+-   [s2RectAdd](./s2.md#s2RectAdd)
+-   [s2RectContains](./s2.md#s2RectContains)
+-   [s2RectUinion](./s2.md#s2RectUinion)
+-   [s2RectIntersection](./s2.md#s2RectIntersection)
+
 
 [Original article](https://clickhouse.com/docs/en/sql-reference/functions/geo/) <!--hide-->

docs/zh/getting-started/tutorial.md

@@ -16,7 +16,14 @@ sidebar_label: 使用教程
 例如，您选择`deb`安装包，执行:
 
 ``` bash
-{% include 'install/deb.sh' %}
+sudo apt-get install -y apt-transport-https ca-certificates dirmngr
+sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 8919F6BD2B48D754
+
+echo "deb https://packages.clickhouse.com/deb stable main" | sudo tee \
+    /etc/apt/sources.list.d/clickhouse.list
+sudo apt-get update
+
+sudo apt-get install -y clickhouse-server clickhouse-client
 ```
 
 在我们安装的软件中包含这些包:

programs/server/Server.cpp

@@ -1488,6 +1488,7 @@ int Server::main(const std::vector<std::string> & /*args*/)
         /// We load temporary database first, because projections need it.
         database_catalog.initializeAndLoadTemporaryDatabase();
         loadMetadataSystem(global_context);
+        maybeConvertOrdinaryDatabaseToAtomic(global_context, DatabaseCatalog::instance().getSystemDatabase());
         /// After attaching system databases we can initialize system log.
         global_context->initializeSystemLogs();
         global_context->setSystemZooKeeperLogAfterInitializationIfNeeded();

src/Core/Settings.h

@@ -445,7 +445,6 @@ static constexpr UInt64 operator""_GiB(unsigned long long value)
     M(Seconds, wait_for_window_view_fire_signal_timeout, 10, "Timeout for waiting for window view fire signal in event time processing", 0) \
     M(UInt64, min_free_disk_space_for_temporary_data, 0, "The minimum disk space to keep while writing temporary data used in external sorting and aggregation.", 0) \
     \
-    M(DefaultDatabaseEngine, default_database_engine, DefaultDatabaseEngine::Atomic, "Default database engine.", 0) \
     M(DefaultTableEngine, default_table_engine, DefaultTableEngine::None, "Default table engine used when ENGINE is not set in CREATE statement.",0) \
     M(Bool, show_table_uuid_in_table_create_query_if_not_nil, false, "For tables in databases with Engine=Atomic show UUID of the table in its CREATE query.", 0) \
     M(Bool, database_atomic_wait_for_drop_and_detach_synchronously, false, "When executing DROP or DETACH TABLE in Atomic database, wait for table data to be finally dropped or detached.", 0) \
@@ -640,6 +639,7 @@ static constexpr UInt64 operator""_GiB(unsigned long long value)
     MAKE_OBSOLETE(M, UInt64, background_schedule_pool_size, 128) \
     MAKE_OBSOLETE(M, UInt64, background_message_broker_schedule_pool_size, 16) \
     MAKE_OBSOLETE(M, UInt64, background_distributed_schedule_pool_size, 16) \
+    MAKE_OBSOLETE(M, DefaultDatabaseEngine, default_database_engine, DefaultDatabaseEngine::Atomic) \
     /** The section above is for obsolete settings. Do not add anything there. */
 
 

src/DataTypes/NestedUtils.cpp

@@ -1,8 +1,10 @@
 #include <cstring>
+#include <memory>
 
 #include <Common/typeid_cast.h>
 #include <Common/assert_cast.h>
 #include <Common/StringUtils/StringUtils.h>
+#include "Columns/IColumn.h"
 
 #include <DataTypes/DataTypeArray.h>
 #include <DataTypes/DataTypeTuple.h>
@@ -17,7 +19,6 @@
 
 #include <boost/algorithm/string/case_conv.hpp>
 
-
 namespace DB
 {
 
@@ -76,8 +77,7 @@ Block flatten(const Block & block)
 
     for (const auto & elem : block)
     {
-        const DataTypeArray * type_arr = typeid_cast<const DataTypeArray *>(elem.type.get());
+        if (const DataTypeArray * type_arr = typeid_cast<const DataTypeArray *>(elem.type.get()))
-        if (type_arr)
         {
             const DataTypeTuple * type_tuple = typeid_cast<const DataTypeTuple *>(type_arr->getNestedType().get());
             if (type_tuple && type_tuple->haveExplicitNames())
@@ -106,7 +106,7 @@ Block flatten(const Block & block)
                     res.insert(ColumnWithTypeAndName(
                         is_const
                             ? ColumnConst::create(std::move(column_array_of_element), block.rows())
-                            : std::move(column_array_of_element),
+                            : column_array_of_element,
                         std::make_shared<DataTypeArray>(element_types[i]),
                         nested_name));
                 }
@@ -114,6 +114,28 @@ Block flatten(const Block & block)
             else
                 res.insert(elem);
         }
+        else if (const DataTypeTuple * type_tuple = typeid_cast<const DataTypeTuple *>(elem.type.get()))
+        {
+            if (type_tuple->haveExplicitNames())
+            {
+                const DataTypes & element_types = type_tuple->getElements();
+                const Strings & names = type_tuple->getElementNames();
+                const ColumnTuple * column_tuple;
+                if (isColumnConst(*elem.column))
+                    column_tuple = typeid_cast<const ColumnTuple *>(&assert_cast<const ColumnConst &>(*elem.column).getDataColumn());
+                else
+                    column_tuple = typeid_cast<const ColumnTuple *>(elem.column.get());
+                size_t tuple_size = column_tuple->tupleSize();
+                for (size_t i = 0; i < tuple_size; ++i)
+                {
+                    const auto & element_column = column_tuple->getColumn(i);
+                    String nested_name = concatenateName(elem.name, names[i]);
+                    res.insert(ColumnWithTypeAndName(element_column.getPtr(), element_types[i], nested_name));
+                }
+            }
+            else
+                res.insert(elem);
+        }
         else
             res.insert(elem);
     }
@@ -243,7 +265,71 @@ std::unordered_set<String> getAllTableNames(const Block & block, bool to_lower_c
     }
     return nested_table_names;
 }
-
 }
 
+NestedColumnExtractHelper::NestedColumnExtractHelper(const Block & block_, bool case_insentive_)
+    : block(block_)
+    , case_insentive(case_insentive_)
+{}
+
+std::optional<ColumnWithTypeAndName> NestedColumnExtractHelper::extractColumn(const String & column_name)
+{
+    if (block.has(column_name, case_insentive))
+        return {block.getByName(column_name, case_insentive)};
+
+    auto nested_names = Nested::splitName(column_name);
+    if (case_insentive)
+    {
+        boost::to_lower(nested_names.first);
+        boost::to_lower(nested_names.second);
+    }
+    if (!block.has(nested_names.first, case_insentive))
+        return {};
+
+    if (!nested_tables.contains(nested_names.first))
+    {
+        ColumnsWithTypeAndName columns = {block.getByName(nested_names.first, case_insentive)};
+        nested_tables[nested_names.first] = std::make_shared<Block>(Nested::flatten(columns));
+    }
+
+    return extractColumn(column_name, nested_names.first, nested_names.second);
+}
+
+std::optional<ColumnWithTypeAndName> NestedColumnExtractHelper::extractColumn(
+    const String & original_column_name, const String & column_name_prefix, const String & column_name_suffix)
+{
+    auto table_iter = nested_tables.find(column_name_prefix);
+    if (table_iter == nested_tables.end())
+    {
+        return {};
+    }
+
+    auto & nested_table = table_iter->second;
+    auto nested_names = Nested::splitName(column_name_suffix);
+    auto new_column_name_prefix = Nested::concatenateName(column_name_prefix, nested_names.first);
+    if (nested_names.second.empty())
+    {
+        if (auto * column_ref = nested_table->findByName(new_column_name_prefix, case_insentive))
+        {
+            ColumnWithTypeAndName column = *column_ref;
+            if (case_insentive)
+                column.name = original_column_name;
+            return {std::move(column)};
+        }
+        else
+        {
+            return {};
+        }
+    }
+
+    if (!nested_table->has(new_column_name_prefix, case_insentive))
+    {
+        return {};
+    }
+
+    ColumnsWithTypeAndName columns = {nested_table->getByName(new_column_name_prefix, case_insentive)};
+    Block sub_block(columns);
+    nested_tables[new_column_name_prefix] = std::make_shared<Block>(Nested::flatten(sub_block));
+    return extractColumn(original_column_name, new_column_name_prefix, nested_names.second);
+}
 }

src/DataTypes/NestedUtils.h

@@ -18,8 +18,9 @@ namespace Nested
     /// Returns the prefix of the name to the first '.'. Or the name is unchanged if there is no dot.
     std::string extractTableName(const std::string & nested_name);
 
-    /// Replace Array(Tuple(...)) columns to a multiple of Array columns in a form of `column_name.element_name`.
+    /// Flat a column of nested type into columns
-    /// only for named tuples that actually represent Nested structures.
+    /// 1) For named tuples，t Tuple(x .., y ..., ...), replace it with t.x ..., t.y ... , ...
+    /// 2) For an Array with named Tuple element column, a Array(Tuple(x ..., y ..., ...)), replace it with multiple Array Columns, a.x ..., a.y ..., ...
     Block flatten(const Block & block);
 
     /// Collect Array columns in a form of `column_name.element_name` to single Array(Tuple(...)) column.
@@ -35,4 +36,20 @@ namespace Nested
     std::unordered_set<String> getAllTableNames(const Block & block, bool to_lower_case = false);
 }
 
+/// Use this class to extract element columns from columns of nested type in a block, e.g. named Tuple.
+/// It can extract a column from a multiple nested type column, e.g. named Tuple in named Tuple
+/// Keeps some intermediate data to avoid rebuild them multi-times.
+class NestedColumnExtractHelper
+{
+public:
+    explicit NestedColumnExtractHelper(const Block & block_, bool case_insentive_);
+    std::optional<ColumnWithTypeAndName> extractColumn(const String & column_name);
+private:
+    std::optional<ColumnWithTypeAndName>
+    extractColumn(const String & original_column_name, const String & column_name_prefix, const String & column_name_suffix);
+    const Block & block;
+    bool case_insentive;
+    std::map<String, BlockPtr> nested_tables;
+};
+
 }

src/Databases/DatabaseAtomic.cpp

@@ -73,7 +73,7 @@ String DatabaseAtomic::getTableDataPath(const ASTCreateQuery & query) const
 
 void DatabaseAtomic::drop(ContextPtr)
 {
-    assert(tables.empty());
+    assert(TSA_SUPPRESS_WARNING_FOR_READ(tables).empty());
     try
     {
         fs::remove(path_to_metadata_symlink);
@@ -90,40 +90,40 @@ void DatabaseAtomic::attachTable(ContextPtr /* context_ */, const String & name,
 {
     assert(relative_table_path != data_path && !relative_table_path.empty());
     DetachedTables not_in_use;
-    std::unique_lock lock(mutex);
+    std::lock_guard lock(mutex);
     not_in_use = cleanupDetachedTables();
     auto table_id = table->getStorageID();
     assertDetachedTableNotInUse(table_id.uuid);
-    DatabaseOrdinary::attachTableUnlocked(name, table, lock);
+    DatabaseOrdinary::attachTableUnlocked(name, table);
     table_name_to_path.emplace(std::make_pair(name, relative_table_path));
 }
 
 StoragePtr DatabaseAtomic::detachTable(ContextPtr /* context */, const String & name)
 {
     DetachedTables not_in_use;
-    std::unique_lock lock(mutex);
+    std::lock_guard lock(mutex);
-    auto table = DatabaseOrdinary::detachTableUnlocked(name, lock);
+    auto table = DatabaseOrdinary::detachTableUnlocked(name);
     table_name_to_path.erase(name);
     detached_tables.emplace(table->getStorageID().uuid, table);
     not_in_use = cleanupDetachedTables(); //-V1001
     return table;
 }
 
-void DatabaseAtomic::dropTable(ContextPtr local_context, const String & table_name, bool no_delay)
+void DatabaseAtomic::dropTable(ContextPtr local_context, const String & table_name, bool sync)
 {
     auto table = tryGetTable(table_name, local_context);
     /// Remove the inner table (if any) to avoid deadlock
     /// (due to attempt to execute DROP from the worker thread)
     if (table)
-        table->dropInnerTableIfAny(no_delay, local_context);
+        table->dropInnerTableIfAny(sync, local_context);
     else
         throw Exception(ErrorCodes::UNKNOWN_TABLE, "Table {}.{} doesn't exist",
-                        backQuote(database_name), backQuote(table_name));
+                        backQuote(getDatabaseName()), backQuote(table_name));
 
     String table_metadata_path = getObjectMetadataPath(table_name);
     String table_metadata_path_drop;
     {
-        std::unique_lock lock(mutex);
+        std::lock_guard lock(mutex);
         table_metadata_path_drop = DatabaseCatalog::instance().getPathForDroppedMetadata(table->getStorageID());
         auto txn = local_context->getZooKeeperMetadataTransaction();
         if (txn && !local_context->isInternalSubquery())
@@ -136,7 +136,7 @@ void DatabaseAtomic::dropTable(ContextPtr local_context, const String & table_na
         /// TODO better detection and recovery
 
         fs::rename(table_metadata_path, table_metadata_path_drop);  /// Mark table as dropped
-        DatabaseOrdinary::detachTableUnlocked(table_name, lock);  /// Should never throw
+        DatabaseOrdinary::detachTableUnlocked(table_name);  /// Should never throw
         table_name_to_path.erase(table_name);
     }
 
@@ -145,11 +145,12 @@ void DatabaseAtomic::dropTable(ContextPtr local_context, const String & table_na
 
     /// Notify DatabaseCatalog that table was dropped. It will remove table data in background.
     /// Cleanup is performed outside of database to allow easily DROP DATABASE without waiting for cleanup to complete.
-    DatabaseCatalog::instance().enqueueDroppedTableCleanup(table->getStorageID(), table, table_metadata_path_drop, no_delay);
+    DatabaseCatalog::instance().enqueueDroppedTableCleanup(table->getStorageID(), table, table_metadata_path_drop, sync);
 }
 
 void DatabaseAtomic::renameTable(ContextPtr local_context, const String & table_name, IDatabase & to_database,
                                  const String & to_table_name, bool exchange, bool dictionary)
+    TSA_NO_THREAD_SAFETY_ANALYSIS   /// TSA does not support conditional locking
 {
     if (typeid(*this) != typeid(to_database))
     {
@@ -173,7 +174,7 @@ void DatabaseAtomic::renameTable(ContextPtr local_context, const String & table_
     String old_metadata_path = getObjectMetadataPath(table_name);
     String new_metadata_path = to_database.getObjectMetadataPath(to_table_name);
 
-    auto detach = [](DatabaseAtomic & db, const String & table_name_, bool has_symlink)
+    auto detach = [](DatabaseAtomic & db, const String & table_name_, bool has_symlink) TSA_REQUIRES(db.mutex)
     {
         auto it = db.table_name_to_path.find(table_name_);
         String table_data_path_saved;
@@ -188,7 +189,7 @@ void DatabaseAtomic::renameTable(ContextPtr local_context, const String & table_
         return table_data_path_saved;
     };
 
-    auto attach = [](DatabaseAtomic & db, const String & table_name_, const String & table_data_path_, const StoragePtr & table_)
+    auto attach = [](DatabaseAtomic & db, const String & table_name_, const String & table_data_path_, const StoragePtr & table_) TSA_REQUIRES(db.mutex)
     {
         db.tables.emplace(table_name_, table_);
         if (table_data_path_.empty())
@@ -229,9 +230,9 @@ void DatabaseAtomic::renameTable(ContextPtr local_context, const String & table_
     }
 
     if (!exchange)
-        other_db.checkMetadataFilenameAvailabilityUnlocked(to_table_name, inside_database ? db_lock : other_db_lock);
+        other_db.checkMetadataFilenameAvailabilityUnlocked(to_table_name);
 
-    StoragePtr table = getTableUnlocked(table_name, db_lock);
+    StoragePtr table = getTableUnlocked(table_name);
 
     if (dictionary && !table->isDictionary())
         throw Exception(ErrorCodes::INCORRECT_QUERY, "Use RENAME/EXCHANGE TABLE (instead of RENAME/EXCHANGE DICTIONARY) for tables");
@@ -244,7 +245,7 @@ void DatabaseAtomic::renameTable(ContextPtr local_context, const String & table_
     StorageID other_table_new_id = StorageID::createEmpty();
     if (exchange)
     {
-        other_table = other_db.getTableUnlocked(to_table_name, other_db_lock);
+        other_table = other_db.getTableUnlocked(to_table_name);
         if (dictionary && !other_table->isDictionary())
             throw Exception(ErrorCodes::INCORRECT_QUERY, "Use RENAME/EXCHANGE TABLE (instead of RENAME/EXCHANGE DICTIONARY) for tables");
         other_table_new_id = {database_name, table_name, other_table->getStorageID().uuid};
@@ -294,7 +295,7 @@ void DatabaseAtomic::commitCreateTable(const ASTCreateQuery & query, const Stora
     auto table_data_path = getTableDataPath(query);
     try
     {
-        std::unique_lock lock{mutex};
+        std::lock_guard lock{mutex};
         if (query.getDatabase() != database_name)
             throw Exception(ErrorCodes::UNKNOWN_DATABASE, "Database was renamed to `{}`, cannot create table in `{}`",
                             database_name, query.getDatabase());
@@ -312,7 +313,7 @@ void DatabaseAtomic::commitCreateTable(const ASTCreateQuery & query, const Stora
 
         /// It throws if `table_metadata_path` already exists (it's possible if table was detached)
         renameNoReplace(table_metadata_tmp_path, table_metadata_path);  /// Commit point (a sort of)
-        attachTableUnlocked(query.getTable(), table, lock);   /// Should never throw
+        attachTableUnlocked(query.getTable(), table);   /// Should never throw
         table_name_to_path.emplace(query.getTable(), table_data_path);
     }
     catch (...)
@@ -330,8 +331,8 @@ void DatabaseAtomic::commitAlterTable(const StorageID & table_id, const String &
     bool check_file_exists = true;
     SCOPE_EXIT({ std::error_code code; if (check_file_exists) std::filesystem::remove(table_metadata_tmp_path, code); });
 
-    std::unique_lock lock{mutex};
+    std::lock_guard lock{mutex};
-    auto actual_table_id = getTableUnlocked(table_id.table_name, lock)->getStorageID();
+    auto actual_table_id = getTableUnlocked(table_id.table_name)->getStorageID();
 
     if (table_id.uuid != actual_table_id.uuid)
         throw Exception("Cannot alter table because it was renamed", ErrorCodes::CANNOT_ASSIGN_ALTER);
@@ -363,7 +364,7 @@ void DatabaseAtomic::assertDetachedTableNotInUse(const UUID & uuid)
 
 void DatabaseAtomic::setDetachedTableNotInUseForce(const UUID & uuid)
 {
-    std::unique_lock lock{mutex};
+    std::lock_guard lock{mutex};
     detached_tables.erase(uuid);
 }
 

src/Databases/DatabaseAtomic.h

@@ -35,7 +35,7 @@ public:
             bool exchange,
             bool dictionary) override;
 
-    void dropTable(ContextPtr context, const String & table_name, bool no_delay) override;
+    void dropTable(ContextPtr context, const String & table_name, bool sync) override;
 
     void attachTable(ContextPtr context, const String & name, const StoragePtr & table, const String & relative_table_path) override;
     StoragePtr detachTable(ContextPtr context, const String & name) override;
@@ -70,9 +70,9 @@ protected:
     void commitCreateTable(const ASTCreateQuery & query, const StoragePtr & table,
                            const String & table_metadata_tmp_path, const String & table_metadata_path, ContextPtr query_context) override;
 
-    void assertDetachedTableNotInUse(const UUID & uuid);
+    void assertDetachedTableNotInUse(const UUID & uuid) TSA_REQUIRES(mutex);
     using DetachedTables = std::unordered_map<UUID, StoragePtr>;
-    [[nodiscard]] DetachedTables cleanupDetachedTables();
+    [[nodiscard]] DetachedTables cleanupDetachedTables() TSA_REQUIRES(mutex);
 
     void tryCreateMetadataSymlink();
 
@@ -80,9 +80,9 @@ protected:
 
     //TODO store path in DatabaseWithOwnTables::tables
     using NameToPathMap = std::unordered_map<String, String>;
-    NameToPathMap table_name_to_path;
+    NameToPathMap table_name_to_path TSA_GUARDED_BY(mutex);
 
-    DetachedTables detached_tables;
+    DetachedTables detached_tables TSA_GUARDED_BY(mutex);
     String path_to_table_symlinks;
     String path_to_metadata_symlink;
     const UUID db_uuid;

src/Databases/DatabaseFactory.cpp

@@ -62,36 +62,19 @@ namespace ErrorCodes
 
 DatabasePtr DatabaseFactory::get(const ASTCreateQuery & create, const String & metadata_path, ContextPtr context)
 {
-    bool created = false;
+    /// Creates store/xxx/ for Atomic
+    fs::create_directories(fs::path(metadata_path).parent_path());
 
-    try
+    DatabasePtr impl = getImpl(create, metadata_path, context);
-    {
-        /// Creates store/xxx/ for Atomic
-        fs::create_directories(fs::path(metadata_path).parent_path());
 
-        /// Before 20.7 it's possible that .sql metadata file does not exist for some old database.
+    if (impl && context->hasQueryContext() && context->getSettingsRef().log_queries)
-        /// In this case Ordinary database is created on server startup if the corresponding metadata directory exists.
+        context->getQueryContext()->addQueryFactoriesInfo(Context::QueryLogFactories::Database, impl->getEngineName());
-        /// So we should remove metadata directory if database creation failed.
-        /// TODO remove this code
-        created = fs::create_directory(metadata_path);
 
-        DatabasePtr impl = getImpl(create, metadata_path, context);
+    /// Attach database metadata
+    if (impl && create.comment)
+        impl->setDatabaseComment(create.comment->as<ASTLiteral>()->value.safeGet<String>());
 
-        if (impl && context->hasQueryContext() && context->getSettingsRef().log_queries)
+    return impl;
-            context->getQueryContext()->addQueryFactoriesInfo(Context::QueryLogFactories::Database, impl->getEngineName());
-
-        // Attach database metadata
-        if (impl && create.comment)
-            impl->setDatabaseComment(create.comment->as<ASTLiteral>()->value.safeGet<String>());
-
-        return impl;
-    }
-    catch (...)
-    {
-        if (created && fs::exists(metadata_path))
-            fs::remove_all(metadata_path);
-        throw;
-    }
 }
 
 template <typename ValueType>
@@ -139,8 +122,14 @@ DatabasePtr DatabaseFactory::getImpl(const ASTCreateQuery & create, const String
         throw Exception(ErrorCodes::BAD_ARGUMENTS, "Database engine `{}` cannot have table overrides", engine_name);
 
     if (engine_name == "Ordinary")
+    {
+        if (!create.attach && !context->getSettingsRef().allow_deprecated_database_ordinary)
+            throw Exception(ErrorCodes::UNKNOWN_DATABASE_ENGINE,
+                            "Ordinary database engine is deprecated (see also allow_deprecated_database_ordinary setting)");
         return std::make_shared<DatabaseOrdinary>(database_name, metadata_path, context);
-    else if (engine_name == "Atomic")
+    }
+
+    if (engine_name == "Atomic")
         return std::make_shared<DatabaseAtomic>(database_name, metadata_path, uuid, context);
     else if (engine_name == "Memory")
         return std::make_shared<DatabaseMemory>(database_name, context);

src/Databases/DatabaseLazy.cpp

@@ -77,10 +77,10 @@ void DatabaseLazy::createTable(
 void DatabaseLazy::dropTable(
     ContextPtr local_context,
     const String & table_name,
-    bool no_delay)
+    bool sync)
 {
     SCOPE_EXIT_MEMORY_SAFE({ clearExpiredTables(); });
-    DatabaseOnDisk::dropTable(local_context, table_name, no_delay);
+    DatabaseOnDisk::dropTable(local_context, table_name, sync);
 }
 
 void DatabaseLazy::renameTable(
@@ -158,6 +158,7 @@ DatabaseTablesIteratorPtr DatabaseLazy::getTablesIterator(ContextPtr, const Filt
 
 bool DatabaseLazy::empty() const
 {
+    std::lock_guard lock(mutex);
     return tables_cache.empty();
 }
 

src/Databases/DatabaseLazy.h

@@ -37,7 +37,7 @@ public:
     void dropTable(
         ContextPtr context,
         const String & table_name,
-        bool no_delay) override;
+        bool sync) override;
 
     void renameTable(
         ContextPtr context,
@@ -102,8 +102,8 @@ private:
     const time_t expiration_time;
 
     /// TODO use DatabaseWithOwnTablesBase::tables
-    mutable TablesCache tables_cache;
+    mutable TablesCache tables_cache TSA_GUARDED_BY(mutex);
-    mutable CacheExpirationQueue cache_expiration_queue;
+    mutable CacheExpirationQueue cache_expiration_queue TSA_GUARDED_BY(mutex);
 
     StoragePtr loadTable(const String & table_name) const;
 

src/Databases/DatabaseMemory.cpp

@@ -32,8 +32,8 @@ void DatabaseMemory::createTable(
     const StoragePtr & table,
     const ASTPtr & query)
 {
-    std::unique_lock lock{mutex};
+    std::lock_guard lock{mutex};
-    attachTableUnlocked(table_name, table, lock);
+    attachTableUnlocked(table_name, table);
 
     /// Clean the query from temporary flags.
     ASTPtr query_to_store = query;
@@ -52,23 +52,24 @@ void DatabaseMemory::createTable(
 void DatabaseMemory::dropTable(
     ContextPtr /*context*/,
     const String & table_name,
-    bool /*no_delay*/)
+    bool /*sync*/)
 {
-    std::unique_lock lock{mutex};
+    StoragePtr table;
-    auto table = detachTableUnlocked(table_name, lock);
+    {
+        std::lock_guard lock{mutex};
+        table = detachTableUnlocked(table_name);
+    }
     try
     {
         /// Remove table without lock since:
         /// - it does not require it
         /// - it may cause lock-order-inversion if underlying storage need to
         ///   resolve tables (like StorageLiveView)
-        SCOPE_EXIT(lock.lock());
-        lock.unlock();
         table->drop();
 
         if (table->storesDataOnDisk())
         {
-            assert(database_name != DatabaseCatalog::TEMPORARY_DATABASE);
+            assert(getDatabaseName() != DatabaseCatalog::TEMPORARY_DATABASE);
             fs::path table_data_dir{getTableDataPath(table_name)};
             if (fs::exists(table_data_dir))
                 fs::remove_all(table_data_dir);
@@ -76,10 +77,13 @@ void DatabaseMemory::dropTable(
     }
     catch (...)
     {
+        std::lock_guard lock{mutex};
         assert(database_name != DatabaseCatalog::TEMPORARY_DATABASE);
-        attachTableUnlocked(table_name, table, lock);
+        attachTableUnlocked(table_name, table);
         throw;
     }
+
+    std::lock_guard lock{mutex};
     table->is_dropped = true;
     create_queries.erase(table_name);
     UUID table_uuid = table->getStorageID().uuid;

src/Databases/DatabaseMemory.h

@@ -32,7 +32,7 @@ public:
     void dropTable(
         ContextPtr context,
         const String & table_name,
-        bool no_delay) override;
+        bool sync) override;
 
     ASTPtr getCreateTableQueryImpl(const String & name, ContextPtr context, bool throw_on_error) const override;
     ASTPtr getCreateDatabaseQuery() const override;
@@ -51,9 +51,9 @@ public:
     void alterTable(ContextPtr local_context, const StorageID & table_id, const StorageInMemoryMetadata & metadata) override;
 
 private:
-    String data_path;
+    const String data_path;
     using NameToASTCreate = std::unordered_map<String, ASTPtr>;
-    NameToASTCreate create_queries;
+    NameToASTCreate create_queries TSA_GUARDED_BY(mutex);
 };
 
 }

src/Databases/DatabaseOnDisk.cpp

@@ -281,7 +281,7 @@ void DatabaseOnDisk::detachTablePermanently(ContextPtr query_context, const Stri
     }
 }
 
-void DatabaseOnDisk::dropTable(ContextPtr local_context, const String & table_name, bool /*no_delay*/)
+void DatabaseOnDisk::dropTable(ContextPtr local_context, const String & table_name, bool /*sync*/)
 {
     String table_metadata_path = getObjectMetadataPath(table_name);
     String table_metadata_path_drop = table_metadata_path + drop_suffix;
@@ -321,11 +321,11 @@ void DatabaseOnDisk::dropTable(ContextPtr local_context, const String & table_na
 
 void DatabaseOnDisk::checkMetadataFilenameAvailability(const String & to_table_name) const
 {
-    std::unique_lock lock(mutex);
+    std::lock_guard lock(mutex);
-    checkMetadataFilenameAvailabilityUnlocked(to_table_name, lock);
+    checkMetadataFilenameAvailabilityUnlocked(to_table_name);
 }
 
-void DatabaseOnDisk::checkMetadataFilenameAvailabilityUnlocked(const String & to_table_name, std::unique_lock<std::mutex> &) const
+void DatabaseOnDisk::checkMetadataFilenameAvailabilityUnlocked(const String & to_table_name) const
 {
     String table_metadata_path = getObjectMetadataPath(to_table_name);
 
@@ -503,7 +503,7 @@ ASTPtr DatabaseOnDisk::getCreateDatabaseQuery() const
 
 void DatabaseOnDisk::drop(ContextPtr local_context)
 {
-    assert(tables.empty());
+    assert(TSA_SUPPRESS_WARNING_FOR_READ(tables).empty());
     if (local_context->getSettingsRef().force_remove_data_recursively_on_drop)
     {
         fs::remove_all(local_context->getPath() + getDataPath());
@@ -725,8 +725,6 @@ ASTPtr DatabaseOnDisk::getCreateQueryFromStorage(const String & table_name, cons
 
 void DatabaseOnDisk::modifySettingsMetadata(const SettingsChanges & settings_changes, ContextPtr query_context)
 {
-    std::lock_guard lock(modify_settings_mutex);
-
     auto create_query = getCreateDatabaseQuery()->clone();
     auto * create = create_query->as<ASTCreateQuery>();
     auto * settings = create->storage->settings;
@@ -759,7 +757,7 @@ void DatabaseOnDisk::modifySettingsMetadata(const SettingsChanges & settings_cha
     writeChar('\n', statement_buf);
     String statement = statement_buf.str();
 
-    String database_name_escaped = escapeForFileName(database_name);
+    String database_name_escaped = escapeForFileName(TSA_SUPPRESS_WARNING_FOR_READ(database_name));   /// FIXME
     fs::path metadata_root_path = fs::canonical(query_context->getGlobalContext()->getPath());
     fs::path metadata_file_tmp_path = fs::path(metadata_root_path) / "metadata" / (database_name_escaped + ".sql.tmp");
     fs::path metadata_file_path = fs::path(metadata_root_path) / "metadata" / (database_name_escaped + ".sql");

src/Databases/DatabaseOnDisk.h

@@ -43,7 +43,7 @@ public:
     void dropTable(
         ContextPtr context,
         const String & table_name,
-        bool no_delay) override;
+        bool sync) override;
 
     void renameTable(
         ContextPtr context,
@@ -70,7 +70,7 @@ public:
 
     /// will throw when the table we want to attach already exists (in active / detached / detached permanently form)
     void checkMetadataFilenameAvailability(const String & to_table_name) const override;
-    void checkMetadataFilenameAvailabilityUnlocked(const String & to_table_name, std::unique_lock<std::mutex> &) const;
+    void checkMetadataFilenameAvailabilityUnlocked(const String & to_table_name) const TSA_REQUIRES(mutex);
 
     void modifySettingsMetadata(const SettingsChanges & settings_changes, ContextPtr query_context);
 
@@ -99,9 +99,6 @@ protected:
 
     const String metadata_path;
     const String data_path;
-
-    /// For alter settings.
-    std::mutex modify_settings_mutex;
 };
 
 }

src/Databases/DatabaseOrdinary.cpp

@@ -174,7 +174,8 @@ void DatabaseOrdinary::loadTablesMetadata(ContextPtr local_context, ParsedTables
             if (ast)
             {
                 auto * create_query = ast->as<ASTCreateQuery>();
-                create_query->setDatabase(database_name);
+                /// NOTE No concurrent writes are possible during database loading
+                create_query->setDatabase(TSA_SUPPRESS_WARNING_FOR_READ(database_name));
 
                 /// Even if we don't load the table we can still mark the uuid of it as taken.
                 if (create_query->uuid != UUIDHelpers::Nil)
@@ -201,7 +202,7 @@ void DatabaseOrdinary::loadTablesMetadata(ContextPtr local_context, ParsedTables
                     return;
                 }
 
-                QualifiedTableName qualified_name{database_name, create_query->getTable()};
+                QualifiedTableName qualified_name{TSA_SUPPRESS_WARNING_FOR_READ(database_name), create_query->getTable()};
                 TableNamesSet loading_dependencies = getDependenciesSetFromCreateQuery(getContext(), qualified_name, ast);
 
                 std::lock_guard lock{metadata.mutex};
@@ -234,12 +235,12 @@ void DatabaseOrdinary::loadTablesMetadata(ContextPtr local_context, ParsedTables
     size_t tables_in_database = objects_in_database - dictionaries_in_database;
 
     LOG_INFO(log, "Metadata processed, database {} has {} tables and {} dictionaries in total.",
-             database_name, tables_in_database, dictionaries_in_database);
+             TSA_SUPPRESS_WARNING_FOR_READ(database_name), tables_in_database, dictionaries_in_database);
 }
 
 void DatabaseOrdinary::loadTableFromMetadata(ContextMutablePtr local_context, const String & file_path, const QualifiedTableName & name, const ASTPtr & ast, bool force_restore)
 {
-    assert(name.database == database_name);
+    assert(name.database == TSA_SUPPRESS_WARNING_FOR_READ(database_name));
     const auto & create_query = ast->as<const ASTCreateQuery &>();
 
     tryAttachTable(
@@ -255,7 +256,8 @@ void DatabaseOrdinary::startupTables(ThreadPool & thread_pool, bool /*force_rest
 {
     LOG_INFO(log, "Starting up tables.");
 
-    const size_t total_tables = tables.size();
+    /// NOTE No concurrent writes are possible during database loading
+    const size_t total_tables = TSA_SUPPRESS_WARNING_FOR_READ(tables).size();
     if (!total_tables)
         return;
 
@@ -271,7 +273,7 @@ void DatabaseOrdinary::startupTables(ThreadPool & thread_pool, bool /*force_rest
 
     try
     {
-        for (const auto & table : tables)
+        for (const auto & table : TSA_SUPPRESS_WARNING_FOR_READ(tables))
             thread_pool.scheduleOrThrowOnError([&]() { startup_one_table(table.second); });
     }
     catch (...)

src/Databases/DatabaseReplicated.cpp

@@ -148,7 +148,7 @@ ClusterPtr DatabaseReplicated::getClusterImpl() const
         if (hosts.empty())
             throw Exception(ErrorCodes::NO_ACTIVE_REPLICAS, "No replicas of database {} found. "
                             "It's possible if the first replica is not fully created yet "
-                            "or if the last replica was just dropped or due to logical error", database_name);
+                            "or if the last replica was just dropped or due to logical error", zookeeper_path);
         Int32 cversion = stat.cversion;
         ::sort(hosts.begin(), hosts.end());
 
@@ -213,7 +213,7 @@ ClusterPtr DatabaseReplicated::getClusterImpl() const
         treat_local_port_as_remote,
         cluster_auth_info.cluster_secure_connection,
         /*priority=*/1,
-        database_name,
+        TSA_SUPPRESS_WARNING_FOR_READ(database_name),     /// FIXME
         cluster_auth_info.cluster_secret);
 }
 
@@ -588,7 +588,7 @@ void DatabaseReplicated::recoverLostReplica(const ZooKeeperPtr & current_zookeep
         query_context->makeQueryContext();
         query_context->getClientInfo().query_kind = ClientInfo::QueryKind::SECONDARY_QUERY;
         query_context->getClientInfo().is_replicated_database_internal = true;
-        query_context->setCurrentDatabase(database_name);
+        query_context->setCurrentDatabase(getDatabaseName());
         query_context->setCurrentQueryId("");
         auto txn = std::make_shared<ZooKeeperMetadataTransaction>(current_zookeeper, zookeeper_path, false, "");
         query_context->initZooKeeperMetadataTransaction(txn);
@@ -608,6 +608,7 @@ void DatabaseReplicated::recoverLostReplica(const ZooKeeperPtr & current_zookeep
         /// and make possible creation of new table with the same UUID.
         String query = fmt::format("CREATE DATABASE IF NOT EXISTS {} ENGINE=Ordinary", backQuoteIfNeed(to_db_name));
         auto query_context = Context::createCopy(getContext());
+        query_context->setSetting("allow_deprecated_database_ordinary", 1);
         executeQuery(query, query_context, true);
 
         /// But we want to avoid discarding UUID of ReplicatedMergeTree tables, because it will not work
@@ -811,7 +812,7 @@ void DatabaseReplicated::shutdown()
 }
 
 
-void DatabaseReplicated::dropTable(ContextPtr local_context, const String & table_name, bool no_delay)
+void DatabaseReplicated::dropTable(ContextPtr local_context, const String & table_name, bool sync)
 {
     auto txn = local_context->getZooKeeperMetadataTransaction();
     assert(!ddl_worker->isCurrentlyActive() || txn || startsWith(table_name, ".inner_id."));
@@ -820,7 +821,7 @@ void DatabaseReplicated::dropTable(ContextPtr local_context, const String & tabl
         String metadata_zk_path = zookeeper_path + "/metadata/" + escapeForFileName(table_name);
         txn->addOp(zkutil::makeRemoveRequest(metadata_zk_path, -1));
     }
-    DatabaseAtomic::dropTable(local_context, table_name, no_delay);
+    DatabaseAtomic::dropTable(local_context, table_name, sync);
 }
 
 void DatabaseReplicated::renameTable(ContextPtr local_context, const String & table_name, IDatabase & to_database,

src/Databases/DatabaseReplicated.h

@@ -30,7 +30,7 @@ public:
     String getEngineName() const override { return "Replicated"; }
 
     /// If current query is initial, then the following methods add metadata updating ZooKeeper operations to current ZooKeeperMetadataTransaction.
-    void dropTable(ContextPtr, const String & table_name, bool no_delay) override;
+    void dropTable(ContextPtr, const String & table_name, bool sync) override;
     void renameTable(ContextPtr context, const String & table_name, IDatabase & to_database,
                      const String & to_table_name, bool exchange, bool dictionary) override;
     void commitCreateTable(const ASTCreateQuery & query, const StoragePtr & table,

src/Databases/DatabasesCommon.cpp

@@ -218,11 +218,11 @@ bool DatabaseWithOwnTablesBase::empty() const
 
 StoragePtr DatabaseWithOwnTablesBase::detachTable(ContextPtr /* context_ */, const String & table_name)
 {
-    std::unique_lock lock(mutex);
+    std::lock_guard lock(mutex);
-    return detachTableUnlocked(table_name, lock);
+    return detachTableUnlocked(table_name);
 }
 
-StoragePtr DatabaseWithOwnTablesBase::detachTableUnlocked(const String & table_name, std::unique_lock<std::mutex> &)
+StoragePtr DatabaseWithOwnTablesBase::detachTableUnlocked(const String & table_name)
 {
     StoragePtr res;
 
@@ -245,11 +245,11 @@ StoragePtr DatabaseWithOwnTablesBase::detachTableUnlocked(const String & table_n
 
 void DatabaseWithOwnTablesBase::attachTable(ContextPtr /* context_ */, const String & table_name, const StoragePtr & table, const String &)
 {
-    std::unique_lock lock(mutex);
+    std::lock_guard lock(mutex);
-    attachTableUnlocked(table_name, table, lock);
+    attachTableUnlocked(table_name, table);
 }
 
-void DatabaseWithOwnTablesBase::attachTableUnlocked(const String & table_name, const StoragePtr & table, std::unique_lock<std::mutex> &)
+void DatabaseWithOwnTablesBase::attachTableUnlocked(const String & table_name, const StoragePtr & table)
 {
     auto table_id = table->getStorageID();
     if (table_id.database_name != database_name)
@@ -313,7 +313,7 @@ DatabaseWithOwnTablesBase::~DatabaseWithOwnTablesBase()
     }
 }
 
-StoragePtr DatabaseWithOwnTablesBase::getTableUnlocked(const String & table_name, std::unique_lock<std::mutex> &) const
+StoragePtr DatabaseWithOwnTablesBase::getTableUnlocked(const String & table_name) const
 {
     auto it = tables.find(table_name);
     if (it != tables.end())

src/Databases/DatabasesCommon.h

@@ -45,14 +45,14 @@ public:
     ~DatabaseWithOwnTablesBase() override;
 
 protected:
-    Tables tables;
+    Tables tables TSA_GUARDED_BY(mutex);
     Poco::Logger * log;
 
     DatabaseWithOwnTablesBase(const String & name_, const String & logger, ContextPtr context);
 
-    void attachTableUnlocked(const String & table_name, const StoragePtr & table, std::unique_lock<std::mutex> & lock);
+    void attachTableUnlocked(const String & table_name, const StoragePtr & table) TSA_REQUIRES(mutex);
-    StoragePtr detachTableUnlocked(const String & table_name, std::unique_lock<std::mutex> & lock);
+    StoragePtr detachTableUnlocked(const String & table_name)  TSA_REQUIRES(mutex);
-    StoragePtr getTableUnlocked(const String & table_name, std::unique_lock<std::mutex> & lock) const;
+    StoragePtr getTableUnlocked(const String & table_name) const TSA_REQUIRES(mutex);
 };
 
 }

src/Databases/IDatabase.cpp

@@ -19,7 +19,7 @@ StoragePtr IDatabase::getTable(const String & name, ContextPtr context) const
 {
     if (auto storage = tryGetTable(name, context))
         return storage;
-    throw Exception(ErrorCodes::UNKNOWN_TABLE, "Table {}.{} doesn't exist", backQuoteIfNeed(database_name), backQuoteIfNeed(name));
+    throw Exception(ErrorCodes::UNKNOWN_TABLE, "Table {}.{} doesn't exist", backQuoteIfNeed(getDatabaseName()), backQuoteIfNeed(name));
 }
 
 ASTPtr IDatabase::getCreateDatabaseQueryForBackup() const

src/Databases/IDatabase.h

@@ -198,7 +198,7 @@ public:
     virtual void dropTable( /// NOLINT
         ContextPtr /*context*/,
         const String & /*name*/,
-        [[maybe_unused]] bool no_delay = false)
+        [[maybe_unused]] bool sync = false)
     {
         throw Exception("There is no DROP TABLE query for Database" + getEngineName(), ErrorCodes::NOT_IMPLEMENTED);
     }
@@ -356,8 +356,8 @@ protected:
     }
 
     mutable std::mutex mutex;
-    String database_name;
+    String database_name TSA_GUARDED_BY(mutex);
-    String comment;
+    String comment TSA_GUARDED_BY(mutex);
 };
 
 using DatabasePtr = std::shared_ptr<IDatabase>;

src/Databases/MySQL/DatabaseMaterializedMySQL.cpp

@@ -80,10 +80,10 @@ void DatabaseMaterializedMySQL::createTable(ContextPtr context_, const String &
     DatabaseAtomic::createTable(context_, name, table, query);
 }
 
-void DatabaseMaterializedMySQL::dropTable(ContextPtr context_, const String & name, bool no_delay)
+void DatabaseMaterializedMySQL::dropTable(ContextPtr context_, const String & name, bool sync)
 {
     checkIsInternalQuery(context_, "DROP TABLE");
-    DatabaseAtomic::dropTable(context_, name, no_delay);
+    DatabaseAtomic::dropTable(context_, name, sync);
 }
 
 void DatabaseMaterializedMySQL::attachTable(ContextPtr context_, const String & name, const StoragePtr & table, const String & relative_table_path)

src/Databases/MySQL/DatabaseMaterializedMySQL.h

@@ -52,7 +52,7 @@ public:
 
     void createTable(ContextPtr context_, const String & name, const StoragePtr & table, const ASTPtr & query) override;
 
-    void dropTable(ContextPtr context_, const String & name, bool no_delay) override;
+    void dropTable(ContextPtr context_, const String & name, bool sync) override;
 
     void attachTable(ContextPtr context_, const String & name, const StoragePtr & table, const String & relative_table_path) override;
 

src/Databases/MySQL/DatabaseMySQL.cpp

@@ -447,7 +447,7 @@ void DatabaseMySQL::detachTablePermanently(ContextPtr, const String & table_name
     table_iter->second.second->is_dropped = true;
 }
 
-void DatabaseMySQL::dropTable(ContextPtr local_context, const String & table_name, bool /*no_delay*/)
+void DatabaseMySQL::dropTable(ContextPtr local_context, const String & table_name, bool /*sync*/)
 {
     detachTablePermanently(local_context, table_name);
 }

src/Databases/MySQL/DatabaseMySQL.h

@@ -82,7 +82,7 @@ public:
 
     void detachTablePermanently(ContextPtr context, const String & table_name) override;
 
-    void dropTable(ContextPtr context, const String & table_name, bool no_delay) override;
+    void dropTable(ContextPtr context, const String & table_name, bool sync) override;
 
     void attachTable(ContextPtr context, const String & table_name, const StoragePtr & storage, const String & relative_table_path) override;
 
@@ -109,15 +109,15 @@ private:
 
     void cleanOutdatedTables();
 
-    void fetchTablesIntoLocalCache(ContextPtr context) const;
+    void fetchTablesIntoLocalCache(ContextPtr context) const TSA_REQUIRES(mutex);
 
     std::map<String, UInt64> fetchTablesWithModificationTime(ContextPtr local_context) const;
 
     std::map<String, ColumnsDescription> fetchTablesColumnsList(const std::vector<String> & tables_name, ContextPtr context) const;
 
-    void destroyLocalCacheExtraTables(const std::map<String, UInt64> & tables_with_modification_time) const;
+    void destroyLocalCacheExtraTables(const std::map<String, UInt64> & tables_with_modification_time) const TSA_REQUIRES(mutex);
 
-    void fetchLatestTablesStructureIntoCache(const std::map<String, UInt64> & tables_modification_time, ContextPtr context) const;
+    void fetchLatestTablesStructureIntoCache(const std::map<String, UInt64> & tables_modification_time, ContextPtr context) const TSA_REQUIRES(mutex);
 
     ThreadFromGlobalPool thread;
 };

src/Databases/PostgreSQL/DatabaseMaterializedPostgreSQL.cpp

@@ -63,9 +63,9 @@ void DatabaseMaterializedPostgreSQL::startSynchronization()
         return;
 
     replication_handler = std::make_unique<PostgreSQLReplicationHandler>(
-            /* replication_identifier */database_name,
+            /* replication_identifier */ TSA_SUPPRESS_WARNING_FOR_READ(database_name),    /// FIXME
             remote_database_name,
-            database_name,
+            TSA_SUPPRESS_WARNING_FOR_READ(database_name),     /// FIXME
             connection_info,
             getContext(),
             is_attach,
@@ -99,7 +99,8 @@ void DatabaseMaterializedPostgreSQL::startSynchronization()
         else
         {
             /// Nested table does not exist and will be created by replication thread.
-            storage = std::make_shared<StorageMaterializedPostgreSQL>(StorageID(database_name, table_name), getContext(), remote_database_name, table_name);
+            /// FIXME TSA
+            storage = std::make_shared<StorageMaterializedPostgreSQL>(StorageID(TSA_SUPPRESS_WARNING_FOR_READ(database_name), table_name), getContext(), remote_database_name, table_name);
         }
 
         /// Cache MaterializedPostgreSQL wrapper over nested table.
@@ -210,7 +211,8 @@ ASTPtr DatabaseMaterializedPostgreSQL::getCreateTableQueryImpl(const String & ta
 
     std::lock_guard lock(handler_mutex);
 
-    auto storage = std::make_shared<StorageMaterializedPostgreSQL>(StorageID(database_name, table_name), getContext(), remote_database_name, table_name);
+    /// FIXME TSA
+    auto storage = std::make_shared<StorageMaterializedPostgreSQL>(StorageID(TSA_SUPPRESS_WARNING_FOR_READ(database_name), table_name), getContext(), remote_database_name, table_name);
     auto ast_storage = replication_handler->getCreateNestedTableQuery(storage.get(), table_name);
     assert_cast<ASTCreateQuery *>(ast_storage.get())->uuid = UUIDHelpers::generateV4();
     return ast_storage;
@@ -234,7 +236,7 @@ ASTPtr DatabaseMaterializedPostgreSQL::createAlterSettingsQuery(const SettingCha
     auto * alter = query->as<ASTAlterQuery>();
 
     alter->alter_object = ASTAlterQuery::AlterObjectType::DATABASE;
-    alter->setDatabase(database_name);
+    alter->setDatabase(TSA_SUPPRESS_WARNING_FOR_READ(database_name));     /// FIXME
     alter->set(alter->command_list, command_list);
 
     return query;
@@ -390,10 +392,10 @@ void DatabaseMaterializedPostgreSQL::stopReplication()
 }
 
 
-void DatabaseMaterializedPostgreSQL::dropTable(ContextPtr local_context, const String & table_name, bool no_delay)
+void DatabaseMaterializedPostgreSQL::dropTable(ContextPtr local_context, const String & table_name, bool sync)
 {
     /// Modify context into nested_context and pass query to Atomic database.
-    DatabaseAtomic::dropTable(StorageMaterializedPostgreSQL::makeNestedTableContext(local_context), table_name, no_delay);
+    DatabaseAtomic::dropTable(StorageMaterializedPostgreSQL::makeNestedTableContext(local_context), table_name, sync);
 }
 
 

src/Databases/PostgreSQL/DatabaseMaterializedPostgreSQL.h

@@ -55,7 +55,7 @@ public:
 
     StoragePtr detachTable(ContextPtr context, const String & table_name) override;
 
-    void dropTable(ContextPtr local_context, const String & name, bool no_delay) override;
+    void dropTable(ContextPtr local_context, const String & name, bool sync) override;
 
     void drop(ContextPtr local_context) override;
 

src/Databases/PostgreSQL/DatabasePostgreSQL.cpp

@@ -264,7 +264,7 @@ void DatabasePostgreSQL::createTable(ContextPtr local_context, const String & ta
 }
 
 
-void DatabasePostgreSQL::dropTable(ContextPtr, const String & table_name, bool /* no_delay */)
+void DatabasePostgreSQL::dropTable(ContextPtr, const String & table_name, bool /* sync */)
 {
     std::lock_guard<std::mutex> lock{mutex};
 
@@ -369,7 +369,11 @@ ASTPtr DatabasePostgreSQL::getCreateDatabaseQuery() const
 
 ASTPtr DatabasePostgreSQL::getCreateTableQueryImpl(const String & table_name, ContextPtr local_context, bool throw_on_error) const
 {
-    auto storage = fetchTable(table_name, local_context, false);
+    StoragePtr storage;
+    {
+        std::lock_guard lock{mutex};
+        storage = fetchTable(table_name, local_context, false);
+    }
     if (!storage)
     {
         if (throw_on_error)

src/Databases/PostgreSQL/DatabasePostgreSQL.h

@@ -53,7 +53,7 @@ public:
     StoragePtr tryGetTable(const String & name, ContextPtr context) const override;
 
     void createTable(ContextPtr, const String & table_name, const StoragePtr & storage, const ASTPtr & create_query) override;
-    void dropTable(ContextPtr, const String & table_name, bool no_delay) override;
+    void dropTable(ContextPtr, const String & table_name, bool sync) override;
 
     void attachTable(ContextPtr context, const String & table_name, const StoragePtr & storage, const String & relative_table_path) override;
     StoragePtr detachTable(ContextPtr context, const String & table_name) override;
@@ -81,7 +81,7 @@ private:
 
     bool checkPostgresTable(const String & table_name) const;
 
-    StoragePtr fetchTable(const String & table_name, ContextPtr context, bool table_checked) const;
+    StoragePtr fetchTable(const String & table_name, ContextPtr context, bool table_checked) const TSA_REQUIRES(mutex);
 
     void removeOutdatedTables();
 

src/Databases/SQLite/DatabaseSQLite.cpp

@@ -173,12 +173,16 @@ ASTPtr DatabaseSQLite::getCreateDatabaseQuery() const
 
 ASTPtr DatabaseSQLite::getCreateTableQueryImpl(const String & table_name, ContextPtr local_context, bool throw_on_error) const
 {
-    auto storage = fetchTable(table_name, local_context, false);
+    StoragePtr storage;
+    {
+        std::lock_guard<std::mutex> lock(mutex);
+        storage = fetchTable(table_name, local_context, false);
+    }
     if (!storage)
     {
         if (throw_on_error)
             throw Exception(ErrorCodes::UNKNOWN_TABLE, "SQLite table {}.{} does not exist",
-                            database_name, table_name);
+                            getDatabaseName(), table_name);
         return nullptr;
     }
     auto table_storage_define = database_engine_define->clone();

src/Databases/SQLite/DatabaseSQLite.h

@@ -54,9 +54,9 @@ private:
 
     bool checkSQLiteTable(const String & table_name) const;
 
-    NameSet fetchTablesList() const;
+    NameSet fetchTablesList() const TSA_REQUIRES(mutex);
 
-    StoragePtr fetchTable(const String & table_name, ContextPtr context, bool table_checked) const;
+    StoragePtr fetchTable(const String & table_name, ContextPtr context, bool table_checked) const TSA_REQUIRES(mutex);
 
 };
 

src/Interpreters/AsynchronousInsertQueue.h

@@ -1,7 +1,6 @@
 #pragma once
 
 #include <Parsers/IAST_fwd.h>
-#include <Common/RWLock.h>
 #include <Common/ThreadPool.h>
 #include <Core/Settings.h>
 #include <Poco/Logger.h>

src/Interpreters/DDLWorker.h

@@ -124,7 +124,7 @@ protected:
     std::string queue_dir;      /// dir with queue of queries
 
     mutable std::mutex zookeeper_mutex;
-    ZooKeeperPtr current_zookeeper;
+    ZooKeeperPtr current_zookeeper TSA_GUARDED_BY(zookeeper_mutex);
 
     /// Save state of executed task to avoid duplicate execution on ZK error
     std::optional<String> last_skipped_entry_name;

src/Interpreters/DatabaseCatalog.cpp

@@ -205,7 +205,10 @@ void DatabaseCatalog::shutdownImpl()
     for (auto & database : current_databases)
         database.second->shutdown();
 
-    tables_marked_dropped.clear();
+    {
+        std::lock_guard lock(tables_marked_dropped_mutex);
+        tables_marked_dropped.clear();
+    }
 
     std::lock_guard lock(databases_mutex);
     for (const auto & db : databases)
@@ -223,6 +226,7 @@ void DatabaseCatalog::shutdownImpl()
             auto & table = mapping.second.second;
             return db || table;
         };
+        std::lock_guard map_lock{elem.mutex};
         auto it = std::find_if(elem.map.begin(), elem.map.end(), not_empty_mapping);
         return it != elem.map.end();
     }) == uuid_map.end());
@@ -689,7 +693,8 @@ DatabaseCatalog::updateDependency(const StorageID & old_from, const StorageID &
 DDLGuardPtr DatabaseCatalog::getDDLGuard(const String & database, const String & table)
 {
     std::unique_lock lock(ddl_guards_mutex);
-    auto db_guard_iter = ddl_guards.try_emplace(database).first;
+    /// TSA does not support unique_lock
+    auto db_guard_iter = TSA_SUPPRESS_WARNING_FOR_WRITE(ddl_guards).try_emplace(database).first;
     DatabaseGuard & db_guard = db_guard_iter->second;
     return std::make_unique<DDLGuard>(db_guard.first, db_guard.second, std::move(lock), table, database);
 }
@@ -999,7 +1004,7 @@ void DatabaseCatalog::waitTableFinallyDropped(const UUID & uuid)
 
     LOG_DEBUG(log, "Waiting for table {} to be finally dropped", toString(uuid));
     std::unique_lock lock{tables_marked_dropped_mutex};
-    wait_table_finally_dropped.wait(lock, [&]()
+    wait_table_finally_dropped.wait(lock, [&]() TSA_REQUIRES(tables_marked_dropped_mutex) -> bool
     {
         return !tables_marked_dropped_ids.contains(uuid);
     });

src/Interpreters/DatabaseCatalog.h

@@ -221,7 +221,7 @@ public:
     DependenciesInfo getLoadingDependenciesInfo(const StorageID & table_id) const;
 
     TableNamesSet tryRemoveLoadingDependencies(const StorageID & table_id, bool check_dependencies, bool is_drop_database = false);
-    TableNamesSet tryRemoveLoadingDependenciesUnlocked(const QualifiedTableName & removing_table, bool check_dependencies, bool is_drop_database = false);
+    TableNamesSet tryRemoveLoadingDependenciesUnlocked(const QualifiedTableName & removing_table, bool check_dependencies, bool is_drop_database = false) TSA_REQUIRES(databases_mutex);
     void checkTableCanBeRemovedOrRenamed(const StorageID & table_id) const;
 
     void updateLoadingDependencies(const StorageID & table_id, TableNamesSet && new_dependencies);
@@ -233,15 +233,15 @@ private:
     static std::unique_ptr<DatabaseCatalog> database_catalog;
 
     explicit DatabaseCatalog(ContextMutablePtr global_context_);
-    void assertDatabaseExistsUnlocked(const String & database_name) const;
+    void assertDatabaseExistsUnlocked(const String & database_name) const TSA_REQUIRES(databases_mutex);
-    void assertDatabaseDoesntExistUnlocked(const String & database_name) const;
+    void assertDatabaseDoesntExistUnlocked(const String & database_name) const TSA_REQUIRES(databases_mutex);
 
     void shutdownImpl();
 
 
     struct UUIDToStorageMapPart
     {
-        std::unordered_map<UUID, DatabaseAndTable> map;
+        std::unordered_map<UUID, DatabaseAndTable> map TSA_GUARDED_BY(mutex);
         mutable std::mutex mutex;
     };
 
@@ -273,12 +273,12 @@ private:
 
     mutable std::mutex databases_mutex;
 
-    ViewDependencies view_dependencies;
+    ViewDependencies view_dependencies TSA_GUARDED_BY(databases_mutex);
 
-    Databases databases;
+    Databases databases TSA_GUARDED_BY(databases_mutex);
     UUIDToStorageMap uuid_map;
 
-    DependenciesInfos loading_dependencies;
+    DependenciesInfos loading_dependencies TSA_GUARDED_BY(databases_mutex);
 
     Poco::Logger * log;
 
@@ -290,12 +290,12 @@ private:
     /// In case the element already exists, waits when query will be executed in other thread. See class DDLGuard below.
     using DatabaseGuard = std::pair<DDLGuard::Map, std::shared_mutex>;
     using DDLGuards = std::map<String, DatabaseGuard>;
-    DDLGuards ddl_guards;
+    DDLGuards ddl_guards TSA_GUARDED_BY(ddl_guards_mutex);
     /// If you capture mutex and ddl_guards_mutex, then you need to grab them strictly in this order.
     mutable std::mutex ddl_guards_mutex;
 
-    TablesMarkedAsDropped tables_marked_dropped;
+    TablesMarkedAsDropped tables_marked_dropped TSA_GUARDED_BY(tables_marked_dropped_mutex);
-    std::unordered_set<UUID> tables_marked_dropped_ids;
+    std::unordered_set<UUID> tables_marked_dropped_ids TSA_GUARDED_BY(tables_marked_dropped_mutex);
     mutable std::mutex tables_marked_dropped_mutex;
 
     std::unique_ptr<BackgroundSchedulePoolTaskHolder> drop_task;

src/Interpreters/HashJoin.h

@@ -16,7 +16,7 @@
 #include <Common/ColumnsHashing.h>
 #include <Common/HashTable/HashMap.h>
 #include <Common/HashTable/FixedHashMap.h>
-#include <Common/RWLock.h>
+#include <Storages/TableLockHolder.h>
 
 #include <Columns/ColumnString.h>
 #include <Columns/ColumnFixedString.h>
@@ -339,7 +339,7 @@ public:
 
     /// We keep correspondence between used_flags and hash table internal buffer.
     /// Hash table cannot be modified during HashJoin lifetime and must be protected with lock.
-    void setLock(RWLockImpl::LockHolder rwlock_holder)
+    void setLock(TableLockHolder rwlock_holder)
     {
         storage_join_lock = rwlock_holder;
     }
@@ -394,7 +394,7 @@ private:
 
     /// Should be set via setLock to protect hash table from modification from StorageJoin
     /// If set HashJoin instance is not available for modification (addJoinedBlock)
-    RWLockImpl::LockHolder storage_join_lock = nullptr;
+    TableLockHolder storage_join_lock = nullptr;
 
     void dataMapInit(MapsVariant &);
 

src/Interpreters/InterpreterCreateIndexQuery.cpp

@@ -0,0 +1,77 @@
+#include <Interpreters/InterpreterCreateIndexQuery.h>
+
+#include <Access/ContextAccess.h>
+#include <Databases/DatabaseReplicated.h>
+#include <Interpreters/Context.h>
+#include <Interpreters/executeDDLQueryOnCluster.h>
+#include <Parsers/ASTCreateIndexQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTIndexDeclaration.h>
+#include <Storages/AlterCommands.h>
+
+namespace DB
+{
+
+namespace ErrorCodes
+{
+    extern const int TABLE_IS_READ_ONLY;
+}
+
+
+BlockIO InterpreterCreateIndexQuery::execute()
+{
+    const auto & create_index = query_ptr->as<ASTCreateIndexQuery &>();
+
+    AccessRightsElements required_access;
+    required_access.emplace_back(AccessType::ALTER_ADD_INDEX, create_index.getDatabase(), create_index.getTable());
+
+    if (!create_index.cluster.empty())
+    {
+        DDLQueryOnClusterParams params;
+        params.access_to_check = std::move(required_access);
+        return executeDDLQueryOnCluster(query_ptr, getContext(), params);
+    }
+
+    getContext()->checkAccess(required_access);
+    auto table_id = getContext()->resolveStorageID(create_index, Context::ResolveOrdinary);
+    query_ptr->as<ASTCreateIndexQuery &>().setDatabase(table_id.database_name);
+
+    DatabasePtr database = DatabaseCatalog::instance().getDatabase(table_id.database_name);
+    if (typeid_cast<DatabaseReplicated *>(database.get())
+        && !getContext()->getClientInfo().is_replicated_database_internal)
+    {
+        auto guard = DatabaseCatalog::instance().getDDLGuard(table_id.database_name, table_id.table_name);
+        guard->releaseTableLock();
+        return typeid_cast<DatabaseReplicated *>(database.get())->tryEnqueueReplicatedDDL(query_ptr, getContext());
+    }
+
+    StoragePtr table = DatabaseCatalog::instance().getTable(table_id, getContext());
+    if (table->isStaticStorage())
+        throw Exception(ErrorCodes::TABLE_IS_READ_ONLY, "Table is read-only");
+
+    /// Convert ASTCreateIndexQuery to AlterCommand.
+    AlterCommands alter_commands;
+
+    AlterCommand command;
+    command.index_decl = create_index.index_decl;
+    command.type = AlterCommand::ADD_INDEX;
+    command.index_name = create_index.index_name->as<ASTIdentifier &>().name();
+    command.if_not_exists = create_index.if_not_exists;
+
+    /// Fill name in ASTIndexDeclaration
+    auto & ast_index_decl = command.index_decl->as<ASTIndexDeclaration &>();
+    ast_index_decl.name = command.index_name;
+
+    alter_commands.emplace_back(std::move(command));
+
+    auto alter_lock = table->lockForAlter(getContext()->getSettingsRef().lock_acquire_timeout);
+    StorageInMemoryMetadata metadata = table->getInMemoryMetadata();
+    alter_commands.validate(table, getContext());
+    alter_commands.prepare(metadata);
+    table->checkAlterIsPossible(alter_commands, getContext());
+    table->alter(alter_commands, getContext(), alter_lock);
+
+    return {};
+}
+
+}

src/Interpreters/InterpreterCreateIndexQuery.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <Interpreters/IInterpreter.h>
+
+
+namespace DB
+{
+
+class Context;
+
+class InterpreterCreateIndexQuery : public IInterpreter, WithContext
+{
+public:
+    InterpreterCreateIndexQuery(const ASTPtr & query_ptr_, ContextPtr context_)
+        : WithContext(context_)
+        , query_ptr(query_ptr_) {}
+
+    BlockIO execute() override;
+
+private:
+    ASTPtr query_ptr;
+};
+
+}

src/Interpreters/InterpreterCreateQuery.cpp

@@ -150,10 +150,9 @@ BlockIO InterpreterCreateQuery::createDatabase(ASTCreateQuery & create)
         /// When attaching old-style database during server startup, we must always use Ordinary engine
         if (create.attach)
             throw Exception("Database engine must be specified for ATTACH DATABASE query", ErrorCodes::UNKNOWN_DATABASE_ENGINE);
-        bool old_style_database = getContext()->getSettingsRef().default_database_engine.value == DefaultDatabaseEngine::Ordinary;
         auto engine = std::make_shared<ASTFunction>();
         auto storage = std::make_shared<ASTStorage>();
-        engine->name = old_style_database ? "Ordinary" : "Atomic";
+        engine->name = "Atomic";
         engine->no_empty_args = true;
         storage->set(storage->engine, engine);
         create.set(create.storage, storage);
@@ -196,8 +195,7 @@ BlockIO InterpreterCreateQuery::createDatabase(ASTCreateQuery & create)
 
         if (create_from_user)
         {
-            const auto & default_engine = getContext()->getSettingsRef().default_database_engine.value;
+            if (create.uuid == UUIDHelpers::Nil)
-            if (create.uuid == UUIDHelpers::Nil && default_engine == DefaultDatabaseEngine::Atomic)
                 create.uuid = UUIDHelpers::generateV4();    /// Will enable Atomic engine for nested database
         }
         else if (attach_from_user && create.uuid == UUIDHelpers::Nil)

src/Interpreters/InterpreterDropIndexQuery.cpp

@@ -0,0 +1,71 @@
+#include <Access/ContextAccess.h>
+#include <Databases/DatabaseReplicated.h>
+#include <Interpreters/Context.h>
+#include <Interpreters/executeDDLQueryOnCluster.h>
+#include <Interpreters/InterpreterDropIndexQuery.h>
+#include <Parsers/ASTDropIndexQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Storages/AlterCommands.h>
+
+namespace DB
+{
+
+namespace ErrorCodes
+{
+    extern const int TABLE_IS_READ_ONLY;
+}
+
+
+BlockIO InterpreterDropIndexQuery::execute()
+{
+    const auto & drop_index = query_ptr->as<ASTDropIndexQuery &>();
+
+    AccessRightsElements required_access;
+    required_access.emplace_back(AccessType::ALTER_DROP_INDEX, drop_index.getDatabase(), drop_index.getTable());
+
+    if (!drop_index.cluster.empty())
+    {
+        DDLQueryOnClusterParams params;
+        params.access_to_check = std::move(required_access);
+        return executeDDLQueryOnCluster(query_ptr, getContext(), params);
+    }
+
+    getContext()->checkAccess(required_access);
+    auto table_id = getContext()->resolveStorageID(drop_index, Context::ResolveOrdinary);
+    query_ptr->as<ASTDropIndexQuery &>().setDatabase(table_id.database_name);
+
+    DatabasePtr database = DatabaseCatalog::instance().getDatabase(table_id.database_name);
+    if (typeid_cast<DatabaseReplicated *>(database.get())
+        && !getContext()->getClientInfo().is_replicated_database_internal)
+    {
+        auto guard = DatabaseCatalog::instance().getDDLGuard(table_id.database_name, table_id.table_name);
+        guard->releaseTableLock();
+        return typeid_cast<DatabaseReplicated *>(database.get())->tryEnqueueReplicatedDDL(query_ptr, getContext());
+    }
+
+    StoragePtr table = DatabaseCatalog::instance().getTable(table_id, getContext());
+    if (table->isStaticStorage())
+        throw Exception(ErrorCodes::TABLE_IS_READ_ONLY, "Table is read-only");
+
+    /// Convert ASTDropIndexQuery to AlterCommand.
+    AlterCommands alter_commands;
+
+    AlterCommand command;
+    command.ast = drop_index.convertToASTAlterCommand();
+    command.type = AlterCommand::DROP_INDEX;
+    command.index_name = drop_index.index_name->as<ASTIdentifier &>().name();
+    command.if_exists = drop_index.if_exists;
+
+    alter_commands.emplace_back(std::move(command));
+
+    auto alter_lock = table->lockForAlter(getContext()->getSettingsRef().lock_acquire_timeout);
+    StorageInMemoryMetadata metadata = table->getInMemoryMetadata();
+    alter_commands.validate(table, getContext());
+    alter_commands.prepare(metadata);
+    table->checkAlterIsPossible(alter_commands, getContext());
+    table->alter(alter_commands, getContext(), alter_lock);
+
+    return {};
+}
+
+}

src/Interpreters/InterpreterDropIndexQuery.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include <Interpreters/IInterpreter.h>
+
+
+namespace DB
+{
+
+class Context;
+
+class InterpreterDropIndexQuery : public IInterpreter, WithContext
+{
+public:
+    InterpreterDropIndexQuery(const ASTPtr & query_ptr_, ContextPtr context_)
+        : WithContext(context_)
+        , query_ptr(query_ptr_) {}
+
+    BlockIO execute() override;
+
+private:
+    ASTPtr query_ptr;
+};
+
+}

src/Interpreters/InterpreterDropQuery.cpp

@@ -62,7 +62,7 @@ BlockIO InterpreterDropQuery::execute()
     }
 
     if (getContext()->getSettingsRef().database_atomic_wait_for_drop_and_detach_synchronously)
-        drop.no_delay = true;
+        drop.sync = true;
 
     if (drop.table)
         return executeToTable(drop);
@@ -89,7 +89,7 @@ BlockIO InterpreterDropQuery::executeToTable(ASTDropQuery & query)
     DatabasePtr database;
     UUID table_to_wait_on = UUIDHelpers::Nil;
     auto res = executeToTableImpl(getContext(), query, database, table_to_wait_on);
-    if (query.no_delay)
+    if (query.sync)
         waitForTableToBeActuallyDroppedOrDetached(query, database, table_to_wait_on);
     return res;
 }
@@ -244,7 +244,7 @@ BlockIO InterpreterDropQuery::executeToTableImpl(ContextPtr context_, ASTDropQue
 
             DatabaseCatalog::instance().tryRemoveLoadingDependencies(table_id, getContext()->getSettingsRef().check_table_dependencies,
                                                                      is_drop_or_detach_database);
-            database->dropTable(context_, table_id.table_name, query.no_delay);
+            database->dropTable(context_, table_id.table_name, query.sync);
         }
 
         db = database;
@@ -300,7 +300,7 @@ BlockIO InterpreterDropQuery::executeToDatabase(const ASTDropQuery & query)
     }
     catch (...)
     {
-        if (query.no_delay)
+        if (query.sync)
         {
             for (const auto & table_uuid : tables_to_wait)
                 waitForTableToBeActuallyDroppedOrDetached(query, database, table_uuid);
@@ -308,7 +308,7 @@ BlockIO InterpreterDropQuery::executeToDatabase(const ASTDropQuery & query)
         throw;
     }
 
-    if (query.no_delay)
+    if (query.sync)
     {
         for (const auto & table_uuid : tables_to_wait)
             waitForTableToBeActuallyDroppedOrDetached(query, database, table_uuid);
@@ -345,7 +345,7 @@ BlockIO InterpreterDropQuery::executeToDatabaseImpl(const ASTDropQuery & query,
                 query_for_table.kind = query.kind;
                 query_for_table.if_exists = true;
                 query_for_table.setDatabase(database_name);
-                query_for_table.no_delay = query.no_delay;
+                query_for_table.sync = query.sync;
 
                 /// Flush should not be done if shouldBeEmptyOnDetach() == false,
                 /// since in this case getTablesIterator() may do some additional work,
@@ -368,7 +368,7 @@ BlockIO InterpreterDropQuery::executeToDatabaseImpl(const ASTDropQuery & query,
                 }
             }
 
-            if (!drop && query.no_delay)
+            if (!drop && query.sync)
             {
                 /// Avoid "some tables are still in use" when sync mode is enabled
                 for (const auto & table_uuid : uuids_to_wait)
@@ -428,7 +428,7 @@ void InterpreterDropQuery::extendQueryLogElemImpl(QueryLogElement & elem, const
     elem.query_kind = "Drop";
 }
 
-void InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind kind, ContextPtr global_context, ContextPtr current_context, const StorageID & target_table_id, bool no_delay)
+void InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind kind, ContextPtr global_context, ContextPtr current_context, const StorageID & target_table_id, bool sync)
 {
     if (DatabaseCatalog::instance().tryGetTable(target_table_id, current_context))
     {
@@ -437,7 +437,7 @@ void InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind kind, ContextPtr
         drop_query->setDatabase(target_table_id.database_name);
         drop_query->setTable(target_table_id.table_name);
         drop_query->kind = kind;
-        drop_query->no_delay = no_delay;
+        drop_query->sync = sync;
         drop_query->if_exists = true;
         ASTPtr ast_drop_query = drop_query;
         /// FIXME We have to use global context to execute DROP query for inner table

src/Interpreters/InterpreterDropQuery.h

@@ -26,7 +26,7 @@ public:
 
     void extendQueryLogElemImpl(QueryLogElement & elem, const ASTPtr &, ContextPtr) const override;
 
-    static void executeDropQuery(ASTDropQuery::Kind kind, ContextPtr global_context, ContextPtr current_context, const StorageID & target_table_id, bool no_delay);
+    static void executeDropQuery(ASTDropQuery::Kind kind, ContextPtr global_context, ContextPtr current_context, const StorageID & target_table_id, bool sync);
 
 private:
     AccessRightsElements getRequiredAccessForDDLOnCluster() const;

src/Interpreters/InterpreterFactory.cpp

@@ -3,7 +3,9 @@
 #include <Parsers/ASTCheckQuery.h>
 #include <Parsers/ASTCreateQuery.h>
 #include <Parsers/ASTCreateFunctionQuery.h>
+#include <Parsers/ASTCreateIndexQuery.h>
 #include <Parsers/ASTDropFunctionQuery.h>
+#include <Parsers/ASTDropIndexQuery.h>
 #include <Parsers/ASTDropQuery.h>
 #include <Parsers/ASTExplainQuery.h>
 #include <Parsers/ASTInsertQuery.h>
@@ -42,10 +44,12 @@
 #include <Interpreters/InterpreterBackupQuery.h>
 #include <Interpreters/InterpreterCheckQuery.h>
 #include <Interpreters/InterpreterCreateFunctionQuery.h>
+#include <Interpreters/InterpreterCreateIndexQuery.h>
 #include <Interpreters/InterpreterCreateQuery.h>
 #include <Interpreters/InterpreterDescribeQuery.h>
 #include <Interpreters/InterpreterDescribeCacheQuery.h>
 #include <Interpreters/InterpreterDropFunctionQuery.h>
+#include <Interpreters/InterpreterDropIndexQuery.h>
 #include <Interpreters/InterpreterDropQuery.h>
 #include <Interpreters/InterpreterExistsQuery.h>
 #include <Interpreters/InterpreterExplainQuery.h>
@@ -298,6 +302,14 @@ std::unique_ptr<IInterpreter> InterpreterFactory::get(ASTPtr & query, ContextMut
     {
         return std::make_unique<InterpreterDropFunctionQuery>(query, context);
     }
+    else if (query->as<ASTCreateIndexQuery>())
+    {
+        return std::make_unique<InterpreterCreateIndexQuery>(query, context);
+    }
+    else if (query->as<ASTDropIndexQuery>())
+    {
+        return std::make_unique<InterpreterDropIndexQuery>(query, context);
+    }
     else if (query->as<ASTBackupQuery>())
     {
         return std::make_unique<InterpreterBackupQuery>(query, context);

src/Interpreters/InterpreterSelectQuery.cpp

@@ -1242,8 +1242,12 @@ void InterpreterSelectQuery::executeImpl(QueryPlan & query_plan, std::optional<P
                 if (expressions.has_order_by)
                     executeOrder(query_plan, input_order_info_for_order);
 
-                if (expressions.has_order_by && query.limitLength())
+                /// pre_distinct = false, because if we have limit and distinct,
-                    executeDistinct(query_plan, false, expressions.selected_columns, true);
+                /// we need to merge streams to one and calculate overall distinct.
+                /// Otherwise we can take several equal values from different streams
+                /// according to limit and skip some distinct values.
+                if (query.limitLength())
+                    executeDistinct(query_plan, false, expressions.selected_columns, false);
 
                 if (expressions.hasLimitBy())
                 {

src/Interpreters/InterpreterSelectWithUnionQuery.cpp

@@ -52,10 +52,6 @@ InterpreterSelectWithUnionQuery::InterpreterSelectWithUnionQuery(
     if (!num_children)
         throw Exception("Logical error: no children in ASTSelectWithUnionQuery", ErrorCodes::LOGICAL_ERROR);
 
-    /// This is required for UNION to match headers correctly.
-    if (num_children > 1)
-        options.reorderColumns();
-
     /// Note that we pass 'required_result_column_names' to first SELECT.
     /// And for the rest, we pass names at the corresponding positions of 'required_result_column_names' in the result of first SELECT,
     ///  because names could be different.
@@ -163,7 +159,22 @@ InterpreterSelectWithUnionQuery::InterpreterSelectWithUnionQuery(
     {
         Blocks headers(num_children);
         for (size_t query_num = 0; query_num < num_children; ++query_num)
+        {
             headers[query_num] = nested_interpreters[query_num]->getSampleBlock();
+            const auto & current_required_result_column_names = required_result_column_names_for_other_selects[query_num];
+            if (!current_required_result_column_names.empty())
+            {
+                const auto & header_columns = headers[query_num].getNames();
+                if (current_required_result_column_names != header_columns)
+                {
+                    throw Exception(ErrorCodes::LOGICAL_ERROR,
+                        "Different order of columns in UNION subquery: {} and {}",
+                        fmt::join(current_required_result_column_names, ", "),
+                        fmt::join(header_columns, ", "));
+                }
+
+            }
+        }
 
         result_header = getCommonHeaderForUnion(headers);
     }

src/Interpreters/MergeTreeTransaction.cpp

@@ -24,16 +24,17 @@ static TableLockHolder getLockForOrdinary(const StoragePtr & storage)
     return storage->lockForShare(RWLockImpl::NO_QUERY, default_timeout);
 }
 
-MergeTreeTransaction::MergeTreeTransaction(CSN snapshot_, LocalTID local_tid_, UUID host_id)
+MergeTreeTransaction::MergeTreeTransaction(CSN snapshot_, LocalTID local_tid_, UUID host_id, std::list<CSN>::iterator snapshot_it_)
     : tid({snapshot_, local_tid_, host_id})
     , snapshot(snapshot_)
+    , snapshot_in_use_it(snapshot_it_)
     , csn(Tx::UnknownCSN)
 {
 }
 
 void MergeTreeTransaction::setSnapshot(CSN new_snapshot)
 {
-    snapshot = new_snapshot;
+    snapshot.store(new_snapshot, std::memory_order_relaxed);
 }
 
 MergeTreeTransaction::State MergeTreeTransaction::getState() const
@@ -219,19 +220,31 @@ void MergeTreeTransaction::afterCommit(CSN assigned_csn) noexcept
     /// It's not a problem if server crash before CSN is written, because we already have TID in data part and entry in the log.
     [[maybe_unused]] CSN prev_value = csn.exchange(assigned_csn);
     chassert(prev_value == Tx::CommittingCSN);
-    for (const auto & part : creating_parts)
+
+    DataPartsVector created_parts;
+    DataPartsVector removed_parts;
+    RunningMutationsList committed_mutations;
+    {
+        /// We don't really need mutex here, because no concurrent modifications of transaction object may happen after commit.
+        std::lock_guard lock{mutex};
+        created_parts = creating_parts;
+        removed_parts = removing_parts;
+        committed_mutations = mutations;
+    }
+
+    for (const auto & part : created_parts)
     {
         part->version.creation_csn.store(csn);
         part->appendCSNToVersionMetadata(VersionMetadata::WhichCSN::CREATION);
     }
 
-    for (const auto & part : removing_parts)
+    for (const auto & part : removed_parts)
     {
         part->version.removal_csn.store(csn);
         part->appendCSNToVersionMetadata(VersionMetadata::WhichCSN::REMOVAL);
     }
 
-    for (const auto & storage_and_mutation : mutations)
+    for (const auto & storage_and_mutation : committed_mutations)
         storage_and_mutation.first->setMutationCSN(storage_and_mutation.second, csn);
 }
 
@@ -313,7 +326,7 @@ void MergeTreeTransaction::onException()
 
 String MergeTreeTransaction::dumpDescription() const
 {
-    String res = fmt::format("{} state: {}, snapshot: {}", tid, getState(), snapshot);
+    String res = fmt::format("{} state: {}, snapshot: {}", tid, getState(), getSnapshot());
 
     if (isReadOnly())
     {
@@ -335,7 +348,7 @@ String MergeTreeTransaction::dumpDescription() const
     {
         String info = fmt::format("{} (created by {}, {})", part->name, part->version.getCreationTID(), part->version.creation_csn);
         std::get<1>(storage_to_changes[&(part->storage)]).push_back(std::move(info));
-        chassert(!part->version.creation_csn || part->version.creation_csn <= snapshot);
+        chassert(!part->version.creation_csn || part->version.creation_csn <= getSnapshot());
     }
 
     for (const auto & mutation : mutations)

src/Interpreters/MergeTreeTransaction.h

@@ -31,13 +31,13 @@ public:
         ROLLED_BACK,
     };
 
-    CSN getSnapshot() const { return snapshot; }
+    CSN getSnapshot() const { return snapshot.load(std::memory_order_relaxed); }
     void setSnapshot(CSN new_snapshot);
     State getState() const;
 
     const TransactionID tid;
 
-    MergeTreeTransaction(CSN snapshot_, LocalTID local_tid_, UUID host_id);
+    MergeTreeTransaction(CSN snapshot_, LocalTID local_tid_, UUID host_id, std::list<CSN>::iterator snapshot_it_);
 
     void addNewPart(const StoragePtr & storage, const DataPartPtr & new_part);
     void removeOldPart(const StoragePtr & storage, const DataPartPtr & part_to_remove, const TransactionInfoContext & context);
@@ -71,16 +71,16 @@ private:
     Stopwatch elapsed;
 
     /// Usually it's equal to tid.start_csn, but can be changed by SET SNAPSHOT query (for introspection purposes and time-traveling)
-    CSN snapshot;
+    std::atomic<CSN> snapshot;
-    std::list<CSN>::iterator snapshot_in_use_it;
+    const std::list<CSN>::iterator snapshot_in_use_it;
 
     /// Lists of changes made by transaction
-    std::unordered_set<StoragePtr> storages;
+    std::unordered_set<StoragePtr> storages TSA_GUARDED_BY(mutex);
-    std::vector<TableLockHolder> table_read_locks_for_ordinary_db;
+    std::vector<TableLockHolder> table_read_locks_for_ordinary_db TSA_GUARDED_BY(mutex);
-    DataPartsVector creating_parts;
+    DataPartsVector creating_parts TSA_GUARDED_BY(mutex);
-    DataPartsVector removing_parts;
+    DataPartsVector removing_parts TSA_GUARDED_BY(mutex);
     using RunningMutationsList = std::vector<std::pair<StoragePtr, String>>;
-    RunningMutationsList mutations;
+    RunningMutationsList mutations TSA_GUARDED_BY(mutex);
 
     std::atomic<CSN> csn;
 };

src/Interpreters/SelectQueryOptions.h

@@ -31,8 +31,6 @@ struct SelectQueryOptions
     bool only_analyze = false;
     bool modify_inplace = false;
     bool remove_duplicates = false;
-    /// This is required for UNION to match headers correctly.
-    bool reorder_columns_as_required_header = false;
     bool ignore_quota = false;
     bool ignore_limits = false;
     /// This flag is needed to analyze query ignoring table projections.
@@ -99,12 +97,6 @@ struct SelectQueryOptions
         return *this;
     }
 
-    SelectQueryOptions & reorderColumns(bool value = true)
-    {
-        reorder_columns_as_required_header = value;
-        return *this;
-    }
-
     SelectQueryOptions & noSubquery()
     {
         subquery_depth = 0;

src/Interpreters/TransactionLog.cpp

@@ -43,16 +43,13 @@ catch (...)
 
 
 TransactionLog::TransactionLog()
-    : log(&Poco::Logger::get("TransactionLog"))
+    : global_context(Context::getGlobalContextInstance())
+    , log(&Poco::Logger::get("TransactionLog"))
+    , zookeeper_path(global_context->getConfigRef().getString("transaction_log.zookeeper_path", "/clickhouse/txn"))
+    , zookeeper_path_log(zookeeper_path + "/log")
+    , fault_probability_before_commit(global_context->getConfigRef().getDouble("transaction_log.fault_probability_before_commit", 0))
+    , fault_probability_after_commit(global_context->getConfigRef().getDouble("transaction_log.fault_probability_after_commit", 0))
 {
-    global_context = Context::getGlobalContextInstance();
-    global_context->checkTransactionsAreAllowed();
-
-    zookeeper_path = global_context->getConfigRef().getString("transaction_log.zookeeper_path", "/clickhouse/txn");
-    zookeeper_path_log = zookeeper_path + "/log";
-    fault_probability_before_commit = global_context->getConfigRef().getDouble("transaction_log.fault_probability_before_commit", 0);
-    fault_probability_after_commit = global_context->getConfigRef().getDouble("transaction_log.fault_probability_after_commit", 0);
-
     loadLogFromZooKeeper();
 
     updating_thread = ThreadFromGlobalPool(&TransactionLog::runUpdatingThread, this);
@@ -128,7 +125,7 @@ void TransactionLog::loadEntries(Strings::const_iterator beg, Strings::const_ite
     LOG_TRACE(log, "Loading {} entries from {}: {}..{}", entries_count, zookeeper_path_log, *beg, last_entry);
     futures.reserve(entries_count);
     for (auto it = beg; it != end; ++it)
-        futures.emplace_back(zookeeper->asyncGet(fs::path(zookeeper_path_log) / *it));
+        futures.emplace_back(TSA_READ_ONE_THREAD(zookeeper)->asyncGet(fs::path(zookeeper_path_log) / *it));
 
     std::vector<std::pair<TIDHash, CSNEntry>> loaded;
     loaded.reserve(entries_count);
@@ -213,7 +210,7 @@ void TransactionLog::runUpdatingThread()
         try
         {
             /// Do not wait if we have some transactions to finalize
-            if (unknown_state_list_loaded.empty())
+            if (TSA_READ_ONE_THREAD(unknown_state_list_loaded).empty())
                 log_updated_event->wait();
 
             if (stop_flag.load())
@@ -230,7 +227,7 @@ void TransactionLog::runUpdatingThread()
 
                 /// It's possible that we connected to different [Zoo]Keeper instance
                 /// so we may read a bit stale state.
-                zookeeper->sync(zookeeper_path_log);
+                TSA_READ_ONE_THREAD(zookeeper)->sync(zookeeper_path_log);
             }
 
             loadNewEntries();
@@ -255,13 +252,13 @@ void TransactionLog::runUpdatingThread()
 
 void TransactionLog::loadNewEntries()
 {
-    Strings entries_list = zookeeper->getChildren(zookeeper_path_log, nullptr, log_updated_event);
+    Strings entries_list = TSA_READ_ONE_THREAD(zookeeper)->getChildren(zookeeper_path_log, nullptr, log_updated_event);
     chassert(!entries_list.empty());
     ::sort(entries_list.begin(), entries_list.end());
-    auto it = std::upper_bound(entries_list.begin(), entries_list.end(), last_loaded_entry);
+    auto it = std::upper_bound(entries_list.begin(), entries_list.end(), TSA_READ_ONE_THREAD(last_loaded_entry));
     loadEntries(it, entries_list.end());
-    chassert(last_loaded_entry == entries_list.back());
+    chassert(TSA_READ_ONE_THREAD(last_loaded_entry) == entries_list.back());
-    chassert(latest_snapshot == deserializeCSN(last_loaded_entry));
+    chassert(latest_snapshot == deserializeCSN(TSA_READ_ONE_THREAD(last_loaded_entry)));
     latest_snapshot.notify_all();
 }
 
@@ -281,7 +278,7 @@ void TransactionLog::removeOldEntries()
 
     /// TODO we will need a bit more complex logic for multiple hosts
     Coordination::Stat stat;
-    CSN old_tail_ptr = deserializeCSN(zookeeper->get(zookeeper_path + "/tail_ptr", &stat));
+    CSN old_tail_ptr = deserializeCSN(TSA_READ_ONE_THREAD(zookeeper)->get(zookeeper_path + "/tail_ptr", &stat));
     CSN new_tail_ptr = getOldestSnapshot();
     if (new_tail_ptr < old_tail_ptr)
         throw Exception(ErrorCodes::LOGICAL_ERROR, "Got unexpected tail_ptr {}, oldest snapshot is {}, it's a bug", old_tail_ptr, new_tail_ptr);
@@ -290,7 +287,7 @@ void TransactionLog::removeOldEntries()
 
     /// (it's not supposed to fail with ZBADVERSION while there is only one host)
     LOG_TRACE(log, "Updating tail_ptr from {} to {}", old_tail_ptr, new_tail_ptr);
-    zookeeper->set(zookeeper_path + "/tail_ptr", serializeCSN(new_tail_ptr), stat.version);
+    TSA_READ_ONE_THREAD(zookeeper)->set(zookeeper_path + "/tail_ptr", serializeCSN(new_tail_ptr), stat.version);
     tail_ptr.store(new_tail_ptr);
 
     /// Now we can find and remove old entries
@@ -314,7 +311,7 @@ void TransactionLog::removeOldEntries()
             continue;
 
         LOG_TEST(log, "Removing entry {} -> {}", elem.second.tid, elem.second.csn);
-        auto code = zookeeper->tryRemove(zookeeper_path_log + "/" + serializeCSN(elem.second.csn));
+        auto code = TSA_READ_ONE_THREAD(zookeeper)->tryRemove(zookeeper_path_log + "/" + serializeCSN(elem.second.csn));
         if (code == Coordination::Error::ZOK || code == Coordination::Error::ZNONODE)
             removed_entries.push_back(elem.first);
     }
@@ -376,11 +373,11 @@ MergeTreeTransactionPtr TransactionLog::beginTransaction()
         std::lock_guard lock{running_list_mutex};
         CSN snapshot = latest_snapshot.load();
         LocalTID ltid = 1 + local_tid_counter.fetch_add(1);
-        txn = std::make_shared<MergeTreeTransaction>(snapshot, ltid, ServerUUID::get());
+        auto snapshot_lock = snapshots_in_use.insert(snapshots_in_use.end(), snapshot);
+        txn = std::make_shared<MergeTreeTransaction>(snapshot, ltid, ServerUUID::get(), snapshot_lock);
         bool inserted = running_list.try_emplace(txn->tid.getHash(), txn).second;
         if (!inserted)
             throw Exception(ErrorCodes::LOGICAL_ERROR, "I's a bug: TID {} {} exists", txn->tid.getHash(), txn->tid);
-        txn->snapshot_in_use_it = snapshots_in_use.insert(snapshots_in_use.end(), snapshot);
     }
 
     LOG_TEST(log, "Beginning transaction {} ({})", txn->tid, txn->tid.getHash());
@@ -595,7 +592,7 @@ TransactionLog::TransactionsList TransactionLog::getTransactionsList() const
 
 void TransactionLog::sync() const
 {
-    Strings entries_list = zookeeper->getChildren(zookeeper_path_log);
+    Strings entries_list = getZooKeeper()->getChildren(zookeeper_path_log);
     chassert(!entries_list.empty());
     ::sort(entries_list.begin(), entries_list.end());
     CSN newest_csn = deserializeCSN(entries_list.back());

src/Interpreters/TransactionLog.h

@@ -129,7 +129,7 @@ public:
     void sync() const;
 
 private:
-    void loadLogFromZooKeeper();
+    void loadLogFromZooKeeper() TSA_REQUIRES(mutex);
     void runUpdatingThread();
 
     void loadEntries(Strings::const_iterator beg, Strings::const_iterator end);
@@ -149,8 +149,8 @@ private:
 
     CSN getCSNImpl(const TIDHash & tid_hash) const;
 
-    ContextPtr global_context;
+    const ContextPtr global_context;
-    Poco::Logger * log;
+    Poco::Logger * const log;
 
     /// The newest snapshot available for reading
     std::atomic<CSN> latest_snapshot;
@@ -167,24 +167,24 @@ private:
         TransactionID tid;
     };
     using TIDMap = std::unordered_map<TIDHash, CSNEntry>;
-    TIDMap tid_to_csn;
+    TIDMap tid_to_csn TSA_GUARDED_BY(mutex);
 
     mutable std::mutex running_list_mutex;
     /// Transactions that are currently processed
-    TransactionsList running_list;
+    TransactionsList running_list TSA_GUARDED_BY(running_list_mutex);
     /// If we lost connection on attempt to create csn- node then we don't know transaction's state.
     using UnknownStateList = std::vector<std::pair<MergeTreeTransaction *, scope_guard>>;
-    UnknownStateList unknown_state_list;
+    UnknownStateList unknown_state_list TSA_GUARDED_BY(running_list_mutex);
-    UnknownStateList unknown_state_list_loaded;
+    UnknownStateList unknown_state_list_loaded TSA_GUARDED_BY(running_list_mutex);
     /// Ordered list of snapshots that are currently used by some transactions. Needed for background cleanup.
-    std::list<CSN> snapshots_in_use;
+    std::list<CSN> snapshots_in_use TSA_GUARDED_BY(running_list_mutex);
 
-    ZooKeeperPtr zookeeper;
+    ZooKeeperPtr zookeeper TSA_GUARDED_BY(mutex);
-    String zookeeper_path;
+    const String zookeeper_path;
 
-    String zookeeper_path_log;
+    const String zookeeper_path_log;
     /// Name of the newest entry that was loaded from log in ZK
-    String last_loaded_entry;
+    String last_loaded_entry TSA_GUARDED_BY(mutex);
     /// The oldest CSN such that we store in log entries with TransactionIDs containing this CSN.
     std::atomic<CSN> tail_ptr = Tx::UnknownCSN;
 
@@ -193,8 +193,8 @@ private:
     std::atomic_bool stop_flag = false;
     ThreadFromGlobalPool updating_thread;
 
-    Float64 fault_probability_before_commit = 0;
+    const Float64 fault_probability_before_commit = 0;
-    Float64 fault_probability_after_commit = 0;
+    const Float64 fault_probability_after_commit = 0;
 };
 
 template <typename Derived>

src/Interpreters/TreeRewriter.cpp

@@ -429,21 +429,28 @@ void renameDuplicatedColumns(const ASTSelectQuery * select_query)
 /// This is the case when we have DISTINCT or arrayJoin: we require more columns in SELECT even if we need less columns in result.
 /// Also we have to remove duplicates in case of GLOBAL subqueries. Their results are placed into tables so duplicates are impossible.
 /// Also remove all INTERPOLATE columns which are not in SELECT anymore.
-void removeUnneededColumnsFromSelectClause(ASTSelectQuery * select_query, const Names & required_result_columns, bool remove_dups, bool reorder_columns_as_required_header)
+void removeUnneededColumnsFromSelectClause(ASTSelectQuery * select_query, const Names & required_result_columns, bool remove_dups)
 {
     ASTs & elements = select_query->select()->children;
 
-    std::map<String, size_t> required_columns_with_duplicate_count;
+    std::unordered_map<String, size_t> required_columns_with_duplicate_count;
+    /// Order of output columns should match order in required_result_columns,
+    /// otherwise UNION queries may have incorrect header when subselect has duplicated columns.
+    ///
+    /// NOTE: multimap is required since there can be duplicated column names.
+    std::unordered_multimap<String, size_t> output_columns_positions;
 
     if (!required_result_columns.empty())
     {
         /// Some columns may be queried multiple times, like SELECT x, y, y FROM table.
-        for (const auto & name : required_result_columns)
+        for (size_t i = 0; i < required_result_columns.size(); ++i)
         {
+            const auto & name = required_result_columns[i];
             if (remove_dups)
                 required_columns_with_duplicate_count[name] = 1;
             else
                 ++required_columns_with_duplicate_count[name];
+            output_columns_positions.emplace(name, i);
         }
     }
     else if (remove_dups)
@@ -455,49 +462,44 @@ void removeUnneededColumnsFromSelectClause(ASTSelectQuery * select_query, const
     else
         return;
 
-    ASTs new_elements;
+    ASTs new_elements(elements.size() + output_columns_positions.size());
-    new_elements.reserve(elements.size());
+    size_t new_elements_size = 0;
 
     NameSet remove_columns;
 
-    /// Resort columns according to required_result_columns.
-    if (reorder_columns_as_required_header && !required_result_columns.empty())
-    {
-        std::unordered_map<String, size_t> name_pos;
-        {
-            size_t pos = 0;
-            for (const auto & name : required_result_columns)
-                name_pos[name] = pos++;
-        }
-        ::sort(elements.begin(), elements.end(), [&](const auto & lhs, const auto & rhs)
-        {
-            String lhs_name = lhs->getAliasOrColumnName();
-            String rhs_name = rhs->getAliasOrColumnName();
-            size_t lhs_pos = name_pos.size();
-            size_t rhs_pos = name_pos.size();
-            if (auto it = name_pos.find(lhs_name); it != name_pos.end())
-                lhs_pos = it->second;
-            if (auto it = name_pos.find(rhs_name); it != name_pos.end())
-                rhs_pos = it->second;
-            return lhs_pos < rhs_pos;
-        });
-    }
-
     for (const auto & elem : elements)
     {
         String name = elem->getAliasOrColumnName();
 
+        /// Columns that are presented in output_columns_positions should
+        /// appears in the same order in the new_elements, hence default
+        /// result_index goes after all elements of output_columns_positions
+        /// (it is for columns that are not located in
+        /// output_columns_positions, i.e. untuple())
+        size_t result_index = output_columns_positions.size() + new_elements_size;
+
+        /// Note, order of duplicated columns is not important here (since they
+        /// are the same), only order for unique columns is important, so it is
+        /// fine to use multimap here.
+        if (auto it = output_columns_positions.find(name); it != output_columns_positions.end())
+        {
+            result_index = it->second;
+            output_columns_positions.erase(it);
+        }
+
         auto it = required_columns_with_duplicate_count.find(name);
         if (required_columns_with_duplicate_count.end() != it && it->second)
         {
-            new_elements.push_back(elem);
+            new_elements[result_index] = elem;
             --it->second;
+            ++new_elements_size;
         }
         else if (select_query->distinct || hasArrayJoin(elem))
         {
             /// ARRAY JOIN cannot be optimized out since it may change number of rows,
             /// so as DISTINCT.
-            new_elements.push_back(elem);
+            new_elements[result_index] = elem;
+            ++new_elements_size;
         }
         else
         {
@@ -508,13 +510,20 @@ void removeUnneededColumnsFromSelectClause(ASTSelectQuery * select_query, const
             /// Never remove untuple. It's result column may be in required columns.
             /// It is not easy to analyze untuple here, because types were not calculated yet.
             if (func && func->name == "untuple")
-                new_elements.push_back(elem);
+            {
-
+                new_elements[result_index] = elem;
+                ++new_elements_size;
+            }
             /// removing aggregation can change number of rows, so `count()` result in outer sub-query would be wrong
             if (func && AggregateUtils::isAggregateFunction(*func) && !select_query->groupBy())
-                new_elements.push_back(elem);
+            {
+                new_elements[result_index] = elem;
+                ++new_elements_size;
+            }
         }
     }
+    /// Remove empty nodes.
+    std::erase(new_elements, ASTPtr{});
 
     if (select_query->interpolate())
     {
@@ -1193,7 +1202,6 @@ TreeRewriterResultPtr TreeRewriter::analyzeSelect(
 
     size_t subquery_depth = select_options.subquery_depth;
     bool remove_duplicates = select_options.remove_duplicates;
-    bool reorder_columns_as_required_header = select_options.reorder_columns_as_required_header;
 
     const auto & settings = getContext()->getSettingsRef();
 
@@ -1245,7 +1253,7 @@ TreeRewriterResultPtr TreeRewriter::analyzeSelect(
     /// Leave all selected columns in case of DISTINCT; columns that contain arrayJoin function inside.
     /// Must be after 'normalizeTree' (after expanding aliases, for aliases not get lost)
     ///  and before 'executeScalarSubqueries', 'analyzeAggregation', etc. to avoid excessive calculations.
-    removeUnneededColumnsFromSelectClause(select_query, required_result_columns, remove_duplicates, reorder_columns_as_required_header);
+    removeUnneededColumnsFromSelectClause(select_query, required_result_columns, remove_duplicates);
 
     /// Executing scalar subqueries - replacing them with constant values.
     executeScalarSubqueries(query, getContext(), subquery_depth, result.scalars, result.local_scalars, select_options.only_analyze);

src/Interpreters/loadMetadata.cpp

@@ -9,6 +9,7 @@
 #include <Interpreters/InterpreterCreateQuery.h>
 #include <Interpreters/Context.h>
 #include <Interpreters/loadMetadata.h>
+#include <Interpreters/executeQuery.h>
 
 #include <Databases/DatabaseOrdinary.h>
 #include <Databases/TablesLoader.h>
@@ -18,7 +19,6 @@
 #include <Common/escapeForFileName.h>
 
 #include <Common/typeid_cast.h>
-#include <Common/StringUtils/StringUtils.h>
 #include <filesystem>
 #include <Common/logger_useful.h>
 
@@ -27,6 +27,12 @@ namespace fs = std::filesystem;
 namespace DB
 {
 
+namespace ErrorCodes
+{
+    extern const int NOT_IMPLEMENTED;
+    extern const int LOGICAL_ERROR;
+}
+
 static void executeCreateQuery(
     const String & query,
     ContextMutablePtr context,
@@ -71,12 +77,6 @@ static void loadDatabase(
         ReadBufferFromFile in(database_metadata_file, 1024);
         readStringUntilEOF(database_attach_query, in);
     }
-    else if (fs::exists(fs::path(database_path)))
-    {
-        /// TODO Remove this code (it's required for compatibility with versions older than 20.7)
-        /// Database exists, but .sql file is absent. It's old-style Ordinary database (e.g. system or default)
-        database_attach_query = "ATTACH DATABASE " + backQuoteIfNeed(database) + " ENGINE = Ordinary";
-    }
     else
     {
         /// It's first server run and we need create default and system databases.
@@ -95,6 +95,15 @@ static void loadDatabase(
     }
 }
 
+static void checkUnsupportedVersion(ContextMutablePtr context, const String & database_name)
+{
+    /// Produce better exception message
+    String metadata_path = context->getPath() + "metadata/" + database_name;
+    if (fs::exists(fs::path(metadata_path)))
+        throw Exception(ErrorCodes::NOT_IMPLEMENTED, "Data directory for {} database exists, but metadata file does not. "
+                                                     "Probably you are trying to upgrade from version older than 20.7. "
+                                                     "If so, you should upgrade through intermediate version.", database_name);
+}
 
 void loadMetadata(ContextMutablePtr context, const String & default_database_name)
 {
@@ -118,43 +127,33 @@ void loadMetadata(ContextMutablePtr context, const String & default_database_nam
         if (it->is_symlink())
             continue;
 
-        const auto current_file = it->path().filename().string();
+        if (it->is_directory())
-        if (!it->is_directory())
-        {
-            /// TODO: DETACH DATABASE PERMANENTLY ?
-            if (fs::path(current_file).extension() == ".sql")
-            {
-                String db_name = fs::path(current_file).stem();
-                if (!isSystemOrInformationSchema(db_name))
-                    databases.emplace(unescapeForFileName(db_name), fs::path(path) / db_name);
-            }
-
-            /// Temporary fails may be left from previous server runs.
-            if (fs::path(current_file).extension() == ".tmp")
-            {
-                LOG_WARNING(log, "Removing temporary file {}", it->path().string());
-                try
-                {
-                    fs::remove(it->path());
-                }
-                catch (...)
-                {
-                    /// It does not prevent server to startup.
-                    tryLogCurrentException(log);
-                }
-            }
-
             continue;
+
+        const auto current_file = it->path().filename().string();
+
+        /// TODO: DETACH DATABASE PERMANENTLY ?
+        if (fs::path(current_file).extension() == ".sql")
+        {
+            String db_name = fs::path(current_file).stem();
+            if (!isSystemOrInformationSchema(db_name))
+                databases.emplace(unescapeForFileName(db_name), fs::path(path) / db_name);
         }
 
-        /// For '.svn', '.gitignore' directory and similar.
+        /// Temporary fails may be left from previous server runs.
-        if (current_file.at(0) == '.')
+        if (fs::path(current_file).extension() == ".tmp")
-            continue;
+        {
-
+            LOG_WARNING(log, "Removing temporary file {}", it->path().string());
-        if (isSystemOrInformationSchema(current_file))
+            try
-            continue;
+            {
-
+                fs::remove(it->path());
-        databases.emplace(unescapeForFileName(current_file), it->path().string());
+            }
+            catch (...)
+            {
+                /// It does not prevent server to startup.
+                tryLogCurrentException(log);
+            }
+        }
     }
 
     /// clickhouse-local creates DatabaseMemory as default database by itself
@@ -162,7 +161,10 @@ void loadMetadata(ContextMutablePtr context, const String & default_database_nam
     bool create_default_db_if_not_exists = !default_database_name.empty();
     bool metadata_dir_for_default_db_already_exists = databases.contains(default_database_name);
     if (create_default_db_if_not_exists && !metadata_dir_for_default_db_already_exists)
+    {
+        checkUnsupportedVersion(context, default_database_name);
         databases.emplace(default_database_name, std::filesystem::path(path) / escapeForFileName(default_database_name));
+    }
 
     TablesLoader::Databases loaded_databases;
     for (const auto & [name, db_path] : databases)
@@ -192,13 +194,14 @@ static void loadSystemDatabaseImpl(ContextMutablePtr context, const String & dat
 {
     String path = context->getPath() + "metadata/" + database_name;
     String metadata_file = path + ".sql";
-    if (fs::exists(fs::path(path)) || fs::exists(fs::path(metadata_file)))
+    if (fs::exists(fs::path(metadata_file)))
     {
         /// 'has_force_restore_data_flag' is true, to not fail on loading query_log table, if it is corrupted.
         loadDatabase(context, database_name, path, true);
     }
     else
     {
+        checkUnsupportedVersion(context, database_name);
         /// Initialize system database manually
         String database_create_query = "CREATE DATABASE ";
         database_create_query += database_name;
@@ -208,6 +211,122 @@ static void loadSystemDatabaseImpl(ContextMutablePtr context, const String & dat
     }
 }
 
+static void convertOrdinaryDatabaseToAtomic(ContextMutablePtr context, const DatabasePtr & database)
+{
+    /// It's kind of C++ script that creates temporary database with Atomic engine,
+    /// moves all tables to it, drops old database and then renames new one to old name.
+
+    Poco::Logger * log = &Poco::Logger::get("loadMetadata");
+
+    String name = database->getDatabaseName();
+
+    String tmp_name = fmt::format(".tmp_convert.{}.{}", name, thread_local_rng());
+
+    String name_quoted = backQuoteIfNeed(name);
+    String tmp_name_quoted = backQuoteIfNeed(tmp_name);
+
+    LOG_INFO(log, "Will convert database {} from Ordinary to Atomic", name_quoted);
+
+    String create_database_query = fmt::format("CREATE DATABASE IF NOT EXISTS {}", tmp_name_quoted);
+    auto res = executeQuery(create_database_query, context, true);
+    executeTrivialBlockIO(res, context);
+    res = {};
+    auto tmp_database = DatabaseCatalog::instance().getDatabase(tmp_name);
+    assert(tmp_database->getEngineName() == "Atomic");
+
+    size_t num_tables = 0;
+    for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next())
+    {
+        ++num_tables;
+        auto id = iterator->table()->getStorageID();
+        id.database_name = tmp_name;
+        iterator->table()->checkTableCanBeRenamed(id);
+    }
+
+    LOG_INFO(log, "Will move {} tables to {}", num_tables, tmp_name_quoted);
+
+    for (auto iterator = database->getTablesIterator(context); iterator->isValid(); iterator->next())
+    {
+        auto id = iterator->table()->getStorageID();
+        String qualified_quoted_name = id.getFullTableName();
+        id.database_name = tmp_name;
+        String tmp_qualified_quoted_name = id.getFullTableName();
+
+        String move_table_query = fmt::format("RENAME TABLE {} TO {}", qualified_quoted_name, tmp_qualified_quoted_name);
+        res = executeQuery(move_table_query, context, true);
+        executeTrivialBlockIO(res, context);
+        res = {};
+    }
+
+    LOG_INFO(log, "Moved all tables from {} to {}", name_quoted, tmp_name_quoted);
+
+    if (!database->empty())
+        throw Exception(ErrorCodes::LOGICAL_ERROR, "Database {} is not empty after moving tables", name_quoted);
+
+    String drop_query = fmt::format("DROP DATABASE {}", name_quoted);
+    res = executeQuery(drop_query, context, true);
+    executeTrivialBlockIO(res, context);
+    res = {};
+
+    String rename_query = fmt::format("RENAME DATABASE {} TO {}", tmp_name_quoted, name_quoted);
+    res = executeQuery(rename_query, context, true);
+    executeTrivialBlockIO(res, context);
+
+    LOG_INFO(log, "Finished database engine conversion of {}", name_quoted);
+}
+
+void maybeConvertOrdinaryDatabaseToAtomic(ContextMutablePtr context, const DatabasePtr & database)
+{
+    if (database->getEngineName() != "Ordinary")
+        return;
+
+    if (context->getSettingsRef().allow_deprecated_database_ordinary)
+        return;
+
+    try
+    {
+        /// It's not quite correct to run DDL queries while database is not started up.
+        startupSystemTables();
+
+        auto local_context = Context::createCopy(context);
+        local_context->setSetting("check_table_dependencies", false);
+        convertOrdinaryDatabaseToAtomic(local_context, database);
+
+        auto new_database = DatabaseCatalog::instance().getDatabase(DatabaseCatalog::SYSTEM_DATABASE);
+        UUID db_uuid = new_database->getUUID();
+        std::vector<UUID> tables_uuids;
+        for (auto iterator = new_database->getTablesIterator(context); iterator->isValid(); iterator->next())
+            tables_uuids.push_back(iterator->uuid());
+
+        /// Reload database just in case (and update logger name)
+        String detach_query = fmt::format("DETACH DATABASE {}", backQuoteIfNeed(DatabaseCatalog::SYSTEM_DATABASE));
+        auto res = executeQuery(detach_query, context, true);
+        executeTrivialBlockIO(res, context);
+        res = {};
+
+        /// Unlock UUID mapping, because it will be locked again on database reload.
+        /// It's safe to do during metadata loading, because cleanup task is not started yet.
+        DatabaseCatalog::instance().removeUUIDMappingFinally(db_uuid);
+        for (const auto & uuid : tables_uuids)
+            DatabaseCatalog::instance().removeUUIDMappingFinally(uuid);
+
+        loadSystemDatabaseImpl(context, DatabaseCatalog::SYSTEM_DATABASE, "Atomic");
+        TablesLoader::Databases databases =
+        {
+            {DatabaseCatalog::SYSTEM_DATABASE, DatabaseCatalog::instance().getSystemDatabase()},
+        };
+        TablesLoader loader{context, databases, /* force_restore */ true, /* force_attach */ true};
+        loader.loadTables();
+
+        /// Will startup tables usual way
+    }
+    catch (Exception & e)
+    {
+        e.addMessage("While trying to convert {} to Atomic", database->getDatabaseName());
+        throw;
+    }
+}
+
 
 void startupSystemTables()
 {

src/Interpreters/loadMetadata.h

@@ -19,4 +19,8 @@ void loadMetadata(ContextMutablePtr context, const String & default_database_nam
 /// so we startup system tables after all databases are loaded.
 void startupSystemTables();
 
+/// Converts database with Ordinary engine to Atomic. Does nothing if database is not Ordinary.
+/// Can be called only during server startup when there are no queries from users.
+void maybeConvertOrdinaryDatabaseToAtomic(ContextMutablePtr context, const DatabasePtr & database);
+
 }

src/Parsers/ASTAlterQuery.cpp

@@ -1,3 +1,4 @@
+#include <Parsers/ASTIndexDeclaration.h>
 #include <iomanip>
 #include <IO/Operators.h>
 #include <Parsers/ASTAlterQuery.h>
@@ -556,6 +557,7 @@ void ASTAlterQuery::formatQueryImpl(const FormatSettings & settings, FormatState
     frame.need_parens = false;
 
     std::string indent_str = settings.one_line ? "" : std::string(4u * frame.indent, ' ');
+
     settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str;
 
     switch (alter_object)

src/Parsers/ASTCreateIndexQuery.cpp

@@ -0,0 +1,61 @@
+#include <Common/quoteString.h>
+#include <IO/Operators.h>
+#include <Parsers/ASTCreateIndexQuery.h>
+#include <Parsers/ASTIndexDeclaration.h>
+
+
+namespace DB
+{
+
+/** Get the text that identifies this element. */
+String ASTCreateIndexQuery::getID(char delim) const
+{
+    return "CreateIndexQuery" + (delim + getDatabase()) + delim + getTable();
+}
+
+ASTPtr ASTCreateIndexQuery::clone() const
+{
+    auto res = std::make_shared<ASTCreateIndexQuery>(*this);
+    res->children.clear();
+
+    res->index_name = index_name->clone();
+    res->children.push_back(res->index_name);
+
+    res->index_decl = index_decl->clone();
+    res->children.push_back(res->index_decl);
+    return res;
+}
+
+void ASTCreateIndexQuery::formatQueryImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const
+{
+    frame.need_parens = false;
+
+    std::string indent_str = settings.one_line ? "" : std::string(4u * frame.indent, ' ');
+
+    settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str;
+
+    settings.ostr << "CREATE INDEX " << (if_not_exists ? "IF NOT EXISTS " : "");
+    index_name->formatImpl(settings, state, frame);
+    settings.ostr << " ON ";
+
+    settings.ostr << (settings.hilite ? hilite_none : "");
+
+    if (table)
+    {
+        if (database)
+        {
+            settings.ostr << indent_str << backQuoteIfNeed(getDatabase());
+            settings.ostr << ".";
+        }
+        settings.ostr << indent_str << backQuoteIfNeed(getTable());
+    }
+
+    formatOnCluster(settings);
+
+    if (!cluster.empty())
+        settings.ostr << " ";
+
+    index_decl->formatImpl(settings, state, frame);
+}
+
+}

src/Parsers/ASTCreateIndexQuery.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <Parsers/ASTQueryWithOnCluster.h>
+#include <Parsers/ASTQueryWithTableAndOutput.h>
+#include <Parsers/IAST.h>
+
+
+namespace DB
+{
+
+/** CREATE INDEX [IF NOT EXISTS] name ON [db].name (expression) TYPE type GRANULARITY value
+ */
+
+class ASTCreateIndexQuery : public ASTQueryWithTableAndOutput, public ASTQueryWithOnCluster
+{
+public:
+    bool if_not_exists{false};
+
+    ASTPtr index_name;
+
+    /// Stores the IndexDeclaration here.
+    ASTPtr index_decl;
+
+    String getID(char delim) const override;
+
+    ASTPtr clone() const override;
+
+    ASTPtr getRewrittenASTWithoutOnCluster(const WithoutOnClusterASTRewriteParams & params) const override
+    {
+        return removeOnCluster<ASTCreateIndexQuery>(clone(), params.default_database);
+    }
+
+    virtual QueryKind getQueryKind() const override { return QueryKind::Create; }
+
+protected:
+    void formatQueryImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
+};
+
+}

src/Parsers/ASTDropIndexQuery.cpp

@@ -0,0 +1,63 @@
+#include <Common/quoteString.h>
+#include <IO/Operators.h>
+#include <Parsers/ASTDropIndexQuery.h>
+
+
+namespace DB
+{
+
+/** Get the text that identifies this element. */
+String ASTDropIndexQuery::getID(char delim) const
+{
+    return "CreateIndexQuery" + (delim + getDatabase()) + delim + getTable();
+}
+
+ASTPtr ASTDropIndexQuery::clone() const
+{
+    auto res = std::make_shared<ASTDropIndexQuery>(*this);
+    res->children.clear();
+
+    res->index_name = index_name->clone();
+    res->children.push_back(res->index_name);
+
+    return res;
+}
+
+void ASTDropIndexQuery::formatQueryImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const
+{
+    frame.need_parens = false;
+
+    std::string indent_str = settings.one_line ? "" : std::string(4u * frame.indent, ' ');
+
+    settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str;
+
+    settings.ostr << "DROP INDEX " << (if_exists ? "IF EXISTS " : "");
+    index_name->formatImpl(settings, state, frame);
+    settings.ostr << " ON ";
+
+    settings.ostr << (settings.hilite ? hilite_none : "");
+
+    if (table)
+    {
+        if (database)
+        {
+            settings.ostr << indent_str << backQuoteIfNeed(getDatabase());
+            settings.ostr << ".";
+        }
+        settings.ostr << indent_str << backQuoteIfNeed(getTable());
+    }
+
+    formatOnCluster(settings);
+}
+
+ASTPtr ASTDropIndexQuery::convertToASTAlterCommand() const
+{
+    auto command = std::make_shared<ASTAlterCommand>();
+    command->index = index_name->clone();
+    command->if_exists = if_exists;
+    command->type = ASTAlterCommand::DROP_INDEX;
+
+    return command;
+}
+
+}

src/Parsers/ASTDropIndexQuery.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include <optional>
+#include <Parsers/ASTAlterQuery.h>
+#include <Parsers/ASTQueryWithOnCluster.h>
+#include <Parsers/ASTQueryWithTableAndOutput.h>
+#include <Parsers/IAST.h>
+#include <Parsers/IParserBase.h>
+
+
+namespace DB
+{
+
+/** DROP INDEX [IF EXISTS] name on [db].name
+ */
+
+class ASTDropIndexQuery : public ASTQueryWithTableAndOutput, public ASTQueryWithOnCluster
+{
+public:
+    bool if_exists{false};
+
+    ASTPtr index_name;
+
+    String getID(char delim) const override;
+
+    ASTPtr clone() const override;
+
+    ASTPtr getRewrittenASTWithoutOnCluster(const WithoutOnClusterASTRewriteParams & params) const override
+    {
+        return removeOnCluster<ASTDropIndexQuery>(clone(), params.default_database);
+    }
+
+    virtual QueryKind getQueryKind() const override { return QueryKind::Drop; }
+
+    /// Convert ASTDropIndexQuery to ASTAlterCommand.
+    ASTPtr convertToASTAlterCommand() const;
+
+protected:
+    void formatQueryImpl(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
+};
+
+}

src/Parsers/ASTDropQuery.cpp

@@ -72,8 +72,8 @@ void ASTDropQuery::formatQueryImpl(const FormatSettings & settings, FormatState
     if (permanently)
         settings.ostr << " PERMANENTLY";
 
-    if (no_delay)
+    if (sync)
-        settings.ostr << (settings.hilite ? hilite_keyword : "") << " NO DELAY" << (settings.hilite ? hilite_none : "");
+        settings.ostr << (settings.hilite ? hilite_keyword : "") << " SYNC" << (settings.hilite ? hilite_none : "");
 }
 
 }

src/Parsers/ASTDropQuery.h

@@ -31,7 +31,7 @@ public:
     /// Same as above
     bool is_view{false};
 
-    bool no_delay{false};
+    bool sync{false};
 
     // We detach the object permanently, so it will not be reattached back during server restart.
     bool permanently{false};

src/Parsers/ASTIndexDeclaration.cpp

@@ -25,9 +25,19 @@ ASTPtr ASTIndexDeclaration::clone() const
 
 void ASTIndexDeclaration::formatImpl(const FormatSettings & s, FormatState & state, FormatStateStacked frame) const
 {
-    s.ostr << backQuoteIfNeed(name);
+    if (from_create_index)
-    s.ostr << " ";
+    {
-    expr->formatImpl(s, state, frame);
+        s.ostr << "(";
+        expr->formatImpl(s, state, frame);
+        s.ostr << ")";
+    }
+    else
+    {
+        s.ostr << backQuoteIfNeed(name);
+        s.ostr << " ";
+        expr->formatImpl(s, state, frame);
+    }
+
     s.ostr << (s.hilite ? hilite_keyword : "") << " TYPE " << (s.hilite ? hilite_none : "");
     type->formatImpl(s, state, frame);
     s.ostr << (s.hilite ? hilite_keyword : "") << " GRANULARITY " << (s.hilite ? hilite_none : "");

src/Parsers/ASTIndexDeclaration.h

@@ -16,6 +16,7 @@ public:
     IAST * expr;
     ASTFunction * type;
     UInt64 granularity;
+    bool from_create_index = false;
 
     /** Get the text that identifies this element. */
     String getID(char) const override { return "Index"; }

src/Parsers/ParserAlterQuery.cpp

@@ -840,7 +840,6 @@ bool ParserAlterCommandList::parseImpl(Pos & pos, ASTPtr & node, Expected & expe
     return true;
 }
 
-
 bool ParserAlterQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
 {
     auto query = std::make_shared<ASTAlterQuery>();

src/Parsers/ParserCreateIndexQuery.cpp

@@ -0,0 +1,120 @@
+#include <Parsers/ParserCreateIndexQuery.h>
+
+#include <Parsers/ASTCreateIndexQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/ASTIndexDeclaration.h>
+#include <Parsers/ASTLiteral.h>
+#include <Parsers/ASTFunction.h>
+#include <Parsers/CommonParsers.h>
+#include <Parsers/ExpressionListParsers.h>
+#include <Parsers/ParserDataType.h>
+#include <Parsers/parseDatabaseAndTableName.h>
+
+namespace DB
+{
+
+bool ParserCreateIndexDeclaration::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
+{
+    ParserKeyword s_type("TYPE");
+    ParserKeyword s_granularity("GRANULARITY");
+
+    ParserDataType data_type_p;
+    ParserExpression expression_p;
+    ParserUnsignedInteger granularity_p;
+
+    ASTPtr expr;
+    ASTPtr type;
+    ASTPtr granularity;
+
+    /// Skip name parser for SQL-standard CREATE INDEX
+    if (!expression_p.parse(pos, expr, expected))
+        return false;
+
+    if (!s_type.ignore(pos, expected))
+        return false;
+
+    if (!data_type_p.parse(pos, type, expected))
+        return false;
+
+    if (!s_granularity.ignore(pos, expected))
+        return false;
+
+    if (!granularity_p.parse(pos, granularity, expected))
+        return false;
+
+    auto index = std::make_shared<ASTIndexDeclaration>();
+    index->from_create_index = true;
+    index->granularity = granularity->as<ASTLiteral &>().value.safeGet<UInt64>();
+    index->set(index->expr, expr);
+    index->set(index->type, type);
+    node = index;
+
+    return true;
+}
+
+bool ParserCreateIndexQuery::parseImpl(IParser::Pos & pos, ASTPtr & node, Expected & expected)
+{
+    auto query = std::make_shared<ASTCreateIndexQuery>();
+    node = query;
+
+    ParserKeyword s_create("CREATE");
+    ParserKeyword s_index("INDEX");
+    ParserKeyword s_if_not_exists("IF NOT EXISTS");
+    ParserKeyword s_on("ON");
+    ParserIdentifier index_name_p;
+    ParserCreateIndexDeclaration parser_create_idx_decl;
+
+    ASTPtr index_name;
+    ASTPtr index_decl;
+
+    String cluster_str;
+    bool if_not_exists = false;
+
+    if (!s_create.ignore(pos, expected))
+        return false;
+
+    if (!s_index.ignore(pos, expected))
+        return false;
+
+    if (s_if_not_exists.ignore(pos, expected))
+        if_not_exists = true;
+
+    if (!index_name_p.parse(pos, index_name, expected))
+        return false;
+
+    /// ON [db.] table_name
+    if (!s_on.ignore(pos, expected))
+        return false;
+
+     if (!parseDatabaseAndTableAsAST(pos, expected, query->database, query->table))
+         return false;
+
+    /// [ON cluster_name]
+     if (s_on.ignore(pos, expected))
+     {
+         if (!ASTQueryWithOnCluster::parse(pos, cluster_str, expected))
+             return false;
+     }
+
+    if (!parser_create_idx_decl.parse(pos, index_decl, expected))
+        return false;
+
+    query->index_name = index_name;
+    query->children.push_back(index_name);
+
+    query->index_decl = index_decl;
+    query->children.push_back(index_decl);
+
+    query->if_not_exists = if_not_exists;
+    query->cluster = cluster_str;
+
+    if (query->database)
+        query->children.push_back(query->database);
+
+    if (query->table)
+        query->children.push_back(query->table);
+
+    return true;
+}
+
+}

src/Parsers/ParserCreateIndexQuery.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <Parsers/IParserBase.h>
+
+namespace DB
+{
+
+/** Query like this:
+  * CREATE INDEX [IF NOT EXISTS] name ON [db].name (expression) TYPE type GRANULARITY value
+  */
+
+class ParserCreateIndexQuery : public IParserBase
+{
+protected:
+    const char * getName() const  override{ return "CREATE INDEX query"; }
+    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
+};
+
+
+/** Parser for index declaration in create index, where name is ignored. */
+class ParserCreateIndexDeclaration : public IParserBase
+{
+public:
+    ParserCreateIndexDeclaration() {}
+
+protected:
+    const char * getName() const override { return "index declaration in create index"; }
+    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
+};
+
+}

src/Parsers/ParserDropIndexQuery.cpp

@@ -0,0 +1,67 @@
+#include <Parsers/ASTDropIndexQuery.h>
+#include <Parsers/ASTIdentifier.h>
+#include <Parsers/CommonParsers.h>
+#include <Parsers/ExpressionElementParsers.h>
+#include <Parsers/ParserDropIndexQuery.h>
+#include <Parsers/parseDatabaseAndTableName.h>
+
+namespace DB
+{
+
+bool ParserDropIndexQuery::parseImpl(IParser::Pos & pos, ASTPtr & node, Expected & expected)
+{
+    auto query = std::make_shared<ASTDropIndexQuery>();
+    node = query;
+
+    ParserKeyword s_drop("DROP");
+    ParserKeyword s_index("INDEX");
+    ParserKeyword s_on("ON");
+    ParserKeyword s_if_exists("IF EXISTS");
+    ParserIdentifier index_name_p;
+
+    String cluster_str;
+    bool if_exists = false;
+
+    if (!s_drop.ignore(pos, expected))
+        return false;
+
+    if (!s_index.ignore(pos, expected))
+        return false;
+
+    if (s_if_exists.ignore(pos, expected))
+        if_exists = true;
+
+    if (!index_name_p.parse(pos, query->index_name, expected))
+        return false;
+
+    /// ON [db.] table_name
+    if (!s_on.ignore(pos, expected))
+        return false;
+
+     if (!parseDatabaseAndTableAsAST(pos, expected, query->database, query->table))
+         return false;
+
+    /// [ON cluster_name]
+     if (s_on.ignore(pos, expected))
+     {
+         if (!ASTQueryWithOnCluster::parse(pos, cluster_str, expected))
+             return false;
+
+        query->cluster = std::move(cluster_str);
+     }
+
+    if (query->index_name)
+        query->children.push_back(query->index_name);
+
+    query->if_exists = if_exists;
+
+    if (query->database)
+        query->children.push_back(query->database);
+
+    if (query->table)
+        query->children.push_back(query->table);
+
+    return true;
+}
+
+}

src/Parsers/ParserDropIndexQuery.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include <Parsers/IParserBase.h>
+
+namespace DB
+{
+
+/** Query like this:
+  * DROP INDEX [IF EXISTS] name ON [db].name
+  */
+
+class ParserDropIndexQuery : public IParserBase
+{
+protected:
+    const char * getName() const  override{ return "DROP INDEX query"; }
+    bool parseImpl(Pos & pos, ASTPtr & node, Expected & expected) override;
+};
+
+}

src/Parsers/ParserDropQuery.cpp

@@ -31,7 +31,7 @@ bool parseDropQuery(IParser::Pos & pos, ASTPtr & node, Expected & expected, cons
     bool temporary = false;
     bool is_dictionary = false;
     bool is_view = false;
-    bool no_delay = false;
+    bool sync = false;
     bool permanently = false;
 
     if (s_database.ignore(pos, expected))
@@ -83,7 +83,7 @@ bool parseDropQuery(IParser::Pos & pos, ASTPtr & node, Expected & expected, cons
 
     /// actually for TRUNCATE NO DELAY / SYNC means nothing
     if (s_no_delay.ignore(pos, expected) || s_sync.ignore(pos, expected))
-        no_delay = true;
+        sync = true;
 
     auto query = std::make_shared<ASTDropQuery>();
     node = query;
@@ -93,7 +93,7 @@ bool parseDropQuery(IParser::Pos & pos, ASTPtr & node, Expected & expected, cons
     query->temporary = temporary;
     query->is_dictionary = is_dictionary;
     query->is_view = is_view;
-    query->no_delay = no_delay;
+    query->sync = sync;
     query->permanently = permanently;
     query->database = database;
     query->table = table;

src/Parsers/ParserQuery.cpp

@@ -2,7 +2,9 @@
 #include <Parsers/ParserCreateFunctionQuery.h>
 #include <Parsers/ParserBackupQuery.h>
 #include <Parsers/ParserCreateQuery.h>
+#include <Parsers/ParserCreateIndexQuery.h>
 #include <Parsers/ParserDropFunctionQuery.h>
+#include <Parsers/ParserDropIndexQuery.h>
 #include <Parsers/ParserDropQuery.h>
 #include <Parsers/ParserInsertQuery.h>
 #include <Parsers/ParserOptimizeQuery.h>
@@ -43,6 +45,8 @@ bool ParserQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
     ParserCreateSettingsProfileQuery create_settings_profile_p;
     ParserCreateFunctionQuery create_function_p;
     ParserDropFunctionQuery drop_function_p;
+    ParserCreateIndexQuery create_index_p;
+    ParserDropIndexQuery drop_index_p;
     ParserDropAccessEntityQuery drop_access_entity_p;
     ParserGrantQuery grant_p;
     ParserSetRoleQuery set_role_p;
@@ -63,6 +67,8 @@ bool ParserQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expected)
         || create_settings_profile_p.parse(pos, node, expected)
         || create_function_p.parse(pos, node, expected)
         || drop_function_p.parse(pos, node, expected)
+        || create_index_p.parse(pos, node, expected)
+        || drop_index_p.parse(pos, node, expected)
         || drop_access_entity_p.parse(pos, node, expected)
         || grant_p.parse(pos, node, expected)
         || external_ddl_p.parse(pos, node, expected)

src/Processors/Formats/Impl/ArrowColumnToCHColumn.cpp

@@ -602,8 +602,8 @@ void ArrowColumnToCHColumn::arrowColumnsToCHChunk(Chunk & res, NameToColumnPtr &
 
     Columns columns_list;
     UInt64 num_rows = name_to_column_ptr.begin()->second->length();
-    columns_list.reserve(header.rows());
+    columns_list.reserve(header.columns());
-    std::unordered_map<String, BlockPtr> nested_tables;
+    std::unordered_map<String, std::pair<BlockPtr, std::shared_ptr<NestedColumnExtractHelper>>> nested_tables;
     bool skipped = false;
     for (size_t column_i = 0, columns = header.columns(); column_i < columns; ++column_i)
     {
@@ -613,55 +613,57 @@ void ArrowColumnToCHColumn::arrowColumnsToCHChunk(Chunk & res, NameToColumnPtr &
         if (case_insensitive_matching)
             boost::to_lower(search_column_name);
 
-        bool read_from_nested = false;
+        ColumnWithTypeAndName column;
-        String nested_table_name = Nested::extractTableName(header_column.name);
-        String search_nested_table_name = nested_table_name;
-        if (case_insensitive_matching)
-            boost::to_lower(search_nested_table_name);
-
         if (!name_to_column_ptr.contains(search_column_name))
         {
+            bool read_from_nested = false;
             /// Check if it's a column from nested table.
-            if (import_nested && name_to_column_ptr.contains(search_nested_table_name))
+            if (import_nested)
             {
-                if (!nested_tables.contains(search_nested_table_name))
+                String nested_table_name = Nested::extractTableName(header_column.name);
+                String search_nested_table_name = nested_table_name;
+                if (case_insensitive_matching)
+                    boost::to_lower(search_nested_table_name);
+                if (name_to_column_ptr.contains(search_nested_table_name))
                 {
-                    std::shared_ptr<arrow::ChunkedArray> arrow_column = name_to_column_ptr[search_nested_table_name];
+                    if (!nested_tables.contains(search_nested_table_name))
-                    ColumnsWithTypeAndName cols
+                    {
-                        = {readColumnFromArrowColumn(arrow_column, nested_table_name, format_name, false, dictionary_values, true, true, false, skipped)};
+                        std::shared_ptr<arrow::ChunkedArray> arrow_column = name_to_column_ptr[search_nested_table_name];
-                    Block block(cols);
+                        ColumnsWithTypeAndName cols = {readColumnFromArrowColumn(
-                    nested_tables[search_nested_table_name] = std::make_shared<Block>(Nested::flatten(block));
+                            arrow_column, nested_table_name, format_name, false, dictionary_values, true, true, false, skipped)};
+                        BlockPtr block_ptr = std::make_shared<Block>(cols);
+                        auto column_extractor = std::make_shared<NestedColumnExtractHelper>(*block_ptr, case_insensitive_matching);
+                        nested_tables[search_nested_table_name] = {block_ptr, column_extractor};
+                    }
+                    auto nested_column = nested_tables[search_nested_table_name].second->extractColumn(search_column_name);
+                    if (nested_column)
+                    {
+                        column = *nested_column;
+                        if (case_insensitive_matching)
+                            column.name = header_column.name;
+                        read_from_nested = true;
+                    }
                 }
-
-                read_from_nested = nested_tables[search_nested_table_name]->has(header_column.name, case_insensitive_matching);
             }
-
             if (!read_from_nested)
             {
                 if (!allow_missing_columns)
                     throw Exception{ErrorCodes::THERE_IS_NO_COLUMN, "Column '{}' is not presented in input data.", header_column.name};
-
+                else
-                ColumnWithTypeAndName column;
+                {
-                column.name = header_column.name;
+                    column.name = header_column.name;
-                column.type = header_column.type;
+                    column.type = header_column.type;
-                column.column = header_column.column->cloneResized(num_rows);
+                    column.column = header_column.column->cloneResized(num_rows);
-                columns_list.push_back(std::move(column.column));
+                    columns_list.push_back(std::move(column.column));
-                continue;
+                    continue;
+                }
             }
         }
-
-
-        ColumnWithTypeAndName column;
-        if (read_from_nested)
-        {
-            column = nested_tables[search_nested_table_name]->getByName(header_column.name, case_insensitive_matching);
-            if (case_insensitive_matching)
-                column.name = header_column.name;
-        }
         else
         {
             auto arrow_column = name_to_column_ptr[search_column_name];
-            column = readColumnFromArrowColumn(arrow_column, header_column.name, format_name, false, dictionary_values, true, true, false, skipped);
+            column = readColumnFromArrowColumn(
+                arrow_column, header_column.name, format_name, false, dictionary_values, true, true, false, skipped);
         }
 
         try
@@ -689,23 +691,17 @@ std::vector<size_t> ArrowColumnToCHColumn::getMissingColumns(const arrow::Schema
 {
     std::vector<size_t> missing_columns;
     auto block_from_arrow = arrowSchemaToCHHeader(schema, format_name, false, &header, case_insensitive_matching);
-    auto flatten_block_from_arrow = Nested::flatten(block_from_arrow);
+    NestedColumnExtractHelper nested_columns_extractor(block_from_arrow, case_insensitive_matching);
 
     for (size_t i = 0, columns = header.columns(); i < columns; ++i)
     {
         const auto & header_column = header.getByPosition(i);
-        bool read_from_nested = false;
-        String nested_table_name = Nested::extractTableName(header_column.name);
         if (!block_from_arrow.has(header_column.name, case_insensitive_matching))
         {
-            if (import_nested && block_from_arrow.has(nested_table_name, case_insensitive_matching))
+            if (!import_nested || !nested_columns_extractor.extractColumn(header_column.name))
-                read_from_nested = flatten_block_from_arrow.has(header_column.name, case_insensitive_matching);
-
-            if (!read_from_nested)
             {
                 if (!allow_missing_columns)
                     throw Exception{ErrorCodes::THERE_IS_NO_COLUMN, "Column '{}' is not presented in input data.", header_column.name};
-
                 missing_columns.push_back(i);
             }
         }

src/Processors/Transforms/DistinctSortedTransform.cpp

@@ -13,10 +13,20 @@ DistinctSortedTransform::DistinctSortedTransform(
     : ISimpleTransform(header_, header_, true)
     , header(std::move(header_))
     , description(std::move(sort_description))
-    , columns_names(columns)
+    , column_names(columns)
     , limit_hint(limit_hint_)
     , set_size_limits(set_size_limits_)
 {
+    /// pre-calculate column positions to use during chunk transformation
+    const size_t num_columns = column_names.empty() ? header.columns() : column_names.size();
+    column_positions.reserve(num_columns);
+    for (size_t i = 0; i < num_columns; ++i)
+    {
+        auto pos = column_names.empty() ? i : header.getPositionByName(column_names[i]);
+        const auto & col = header.getByPosition(pos).column;
+        if (col && !isColumnConst(*col))
+            column_positions.emplace_back(pos);
+    }
 }
 
 void DistinctSortedTransform::transform(Chunk & chunk)
@@ -119,24 +129,13 @@ bool DistinctSortedTransform::buildFilter(
 
 ColumnRawPtrs DistinctSortedTransform::getKeyColumns(const Chunk & chunk) const
 {
-    size_t columns = columns_names.empty() ? chunk.getNumColumns() : columns_names.size();
-
     ColumnRawPtrs column_ptrs;
-    column_ptrs.reserve(columns);
+    column_ptrs.reserve(column_positions.size());
-
+    for (const auto pos : column_positions)
-    for (size_t i = 0; i < columns; ++i)
     {
-        auto pos = i;
-        if (!columns_names.empty())
-            pos = input.getHeader().getPositionByName(columns_names[i]);
-
         const auto & column = chunk.getColumns()[pos];
-
+        column_ptrs.emplace_back(column.get());
-        /// Ignore all constant columns.
-        if (!isColumnConst(*column))
-            column_ptrs.emplace_back(column.get());
     }
-
     return column_ptrs;
 }
 

src/Processors/Transforms/DistinctSortedTransform.h

@@ -3,6 +3,7 @@
 #include <Processors/ISimpleTransform.h>
 #include <Interpreters/SetVariants.h>
 #include <Core/SortDescription.h>
+#include <Core/ColumnNumbers.h>
 
 
 namespace DB
@@ -57,7 +58,8 @@ private:
     };
     PreviousChunk prev_chunk;
 
-    Names columns_names;
+    Names column_names;
+    ColumnNumbers column_positions;
     ClearableSetVariants data;
     Sizes key_sizes;
     UInt64 limit_hint;

src/Storages/Hive/StorageHive.cpp

@@ -37,6 +37,7 @@
 #include <Storages/Hive/StorageHiveMetadata.h>
 #include <Storages/MergeTree/KeyCondition.h>
 #include <Storages/StorageFactory.h>
+#include <DataTypes/NestedUtils.h>
 
 namespace DB
 {
@@ -766,8 +767,20 @@ Pipe StorageHive::read(
     sources_info->hive_metastore_client = hive_metastore_client;
     sources_info->partition_name_types = partition_name_types;
 
-    Block sample_block;
     const auto header_block = storage_snapshot->metadata->getSampleBlock();
+    bool support_subset_columns = supportsSubcolumns();
+
+    auto settings = context_->getSettingsRef();
+    auto case_insensitive_matching = [&]() -> bool
+    {
+        if (format_name == "Parquet")
+            return settings.input_format_parquet_case_insensitive_column_matching;
+        else if (format_name == "ORC")
+            return settings.input_format_orc_case_insensitive_column_matching;
+        return false;
+    };
+    Block sample_block;
+    NestedColumnExtractHelper nested_columns_extractor(header_block, case_insensitive_matching());
     for (const auto & column : column_names)
     {
         if (header_block.has(column))
@@ -775,7 +788,15 @@ Pipe StorageHive::read(
             sample_block.insert(header_block.getByName(column));
             continue;
         }
-
+        else if (support_subset_columns)
+        {
+            auto subset_column = nested_columns_extractor.extractColumn(column);
+            if (subset_column)
+            {
+                sample_block.insert(std::move(*subset_column));
+                continue;
+            }
+        }
         if (column == "_path")
             sources_info->need_path_column = true;
         if (column == "_file")

src/Storages/Hive/StorageHive.h

@@ -42,6 +42,9 @@ public:
     String getName() const override { return "Hive"; }
 
     bool supportsIndexForIn() const override { return true; }
+
+    bool supportsSubcolumns() const override { return true; }
+
     bool mayBenefitFromIndexForIn(
         const ASTPtr & /* left_in_operand */,
         ContextPtr /* query_context */,

src/Storages/IStorage.h

@@ -396,7 +396,7 @@ public:
       */
     virtual void drop() {}
 
-    virtual void dropInnerTableIfAny(bool /* no_delay */, ContextPtr /* context */) {}
+    virtual void dropInnerTableIfAny(bool /* sync */, ContextPtr /* context */) {}
 
     /** Clear the table data and leave it empty.
       * Must be called under exclusive lock (lockExclusively).

src/Storages/MergeTree/MergeTreeData.cpp

@@ -1324,20 +1324,29 @@ void MergeTreeData::loadDataParts(bool skip_sanity_checks)
 
     auto deactivate_part = [&] (DataPartIteratorByStateAndInfo it)
     {
+        const DataPartPtr & part = *it;
 
-        (*it)->remove_time.store((*it)->modification_time, std::memory_order_relaxed);
+        part->remove_time.store(part->modification_time, std::memory_order_relaxed);
-        auto creation_csn = (*it)->version.creation_csn.load(std::memory_order_relaxed);
+        auto creation_csn = part->version.creation_csn.load(std::memory_order_relaxed);
-        if (creation_csn != Tx::RolledBackCSN && creation_csn != Tx::PrehistoricCSN && !(*it)->version.isRemovalTIDLocked())
+        if (creation_csn != Tx::RolledBackCSN && creation_csn != Tx::PrehistoricCSN && !part->version.isRemovalTIDLocked())
         {
             /// It's possible that covering part was created without transaction,
             /// but if covered part was created with transaction (i.e. creation_tid is not prehistoric),
             /// then it must have removal tid in metadata file.
             throw Exception(ErrorCodes::LOGICAL_ERROR, "Data part {} is Outdated and has creation TID {} and CSN {}, "
                             "but does not have removal tid. It's a bug or a result of manual intervention.",
-                            (*it)->name, (*it)->version.creation_tid, creation_csn);
+                            part->name, part->version.creation_tid, creation_csn);
         }
         modifyPartState(it, DataPartState::Outdated);
-        removePartContributionToDataVolume(*it);
+        removePartContributionToDataVolume(part);
+
+        /// Explicitly set removal_tid_lock for parts w/o transaction (i.e. w/o txn_version.txt)
+        /// to avoid keeping part forever (see VersionMetadata::canBeRemoved())
+        if (!part->version.isRemovalTIDLocked())
+        {
+            TransactionInfoContext transaction_context{getStorageID(), part->name};
+            part->version.lockRemovalTID(Tx::PrehistoricTID, transaction_context);
+        }
     };
 
     /// All parts are in "Active" state after loading

src/Storages/MergeTree/registerStorageMergeTree.cpp

@@ -304,12 +304,22 @@ static StoragePtr create(const StorageFactory::Arguments & args)
                             arg_idx, e.message(), getMergeTreeVerboseHelp(is_extended_storage_def));
         }
     }
+    else if (!args.attach && !args.getLocalContext()->getSettingsRef().allow_deprecated_syntax_for_merge_tree)
+    {
+        throw Exception(ErrorCodes::BAD_ARGUMENTS, "This syntax for *MergeTree engine is deprecated. "
+                                                   "Use extended storage definition syntax with ORDER BY/PRIMARY KEY clause."
+                                                   "See also allow_deprecated_syntax_for_merge_tree setting.");
+    }
 
     /// For Replicated.
     String zookeeper_path;
     String replica_name;
     StorageReplicatedMergeTree::RenamingRestrictions renaming_restrictions = StorageReplicatedMergeTree::RenamingRestrictions::ALLOW_ANY;
 
+    bool is_on_cluster = args.getLocalContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY;
+    bool is_replicated_database = args.getLocalContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY &&
+        DatabaseCatalog::instance().getDatabase(args.table_id.database_name)->getEngineName() == "Replicated";
+
     if (replicated)
     {
         bool has_arguments = arg_num + 2 <= arg_cnt;
@@ -372,17 +382,11 @@ static StoragePtr create(const StorageFactory::Arguments & args)
             throw Exception("Expected two string literal arguments: zookeeper_path and replica_name", ErrorCodes::BAD_ARGUMENTS);
 
         /// Allow implicit {uuid} macros only for zookeeper_path in ON CLUSTER queries
-        bool is_on_cluster = args.getLocalContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY;
-        bool is_replicated_database = args.getLocalContext()->getClientInfo().query_kind == ClientInfo::QueryKind::SECONDARY_QUERY &&
-                                      DatabaseCatalog::instance().getDatabase(args.table_id.database_name)->getEngineName() == "Replicated";
         bool allow_uuid_macro = is_on_cluster || is_replicated_database || args.query.attach;
 
         /// Unfold {database} and {table} macro on table creation, so table can be renamed.
         if (!args.attach)
         {
-            if (is_replicated_database && !is_extended_storage_def)
-                throw Exception(ErrorCodes::BAD_ARGUMENTS, "Old syntax is not allowed for ReplicatedMergeTree tables in Replicated databases");
-
             Macros::MacroExpansionInfo info;
             /// NOTE: it's not recursive
             info.expand_special_macros_only = true;

src/Storages/PostgreSQL/StorageMaterializedPostgreSQL.cpp

@@ -240,7 +240,7 @@ void StorageMaterializedPostgreSQL::shutdown()
 }
 
 
-void StorageMaterializedPostgreSQL::dropInnerTableIfAny(bool no_delay, ContextPtr local_context)
+void StorageMaterializedPostgreSQL::dropInnerTableIfAny(bool sync, ContextPtr local_context)
 {
     /// If it is a table with database engine MaterializedPostgreSQL - return, because delition of
     /// internal tables is managed there.
@@ -252,7 +252,7 @@ void StorageMaterializedPostgreSQL::dropInnerTableIfAny(bool no_delay, ContextPt
 
     auto nested_table = tryGetNested() != nullptr;
     if (nested_table)
-        InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, getNestedStorageID(), no_delay);
+        InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, getNestedStorageID(), sync);
 }
 
 

src/Storages/PostgreSQL/StorageMaterializedPostgreSQL.h

@@ -84,7 +84,7 @@ public:
     void shutdown() override;
 
     /// Used only for single MaterializedPostgreSQL storage.
-    void dropInnerTableIfAny(bool no_delay, ContextPtr local_context) override;
+    void dropInnerTableIfAny(bool sync, ContextPtr local_context) override;
 
     NamesAndTypesList getVirtuals() const override;
 

src/Storages/RabbitMQ/RabbitMQSource.cpp

@@ -142,7 +142,7 @@ Chunk RabbitMQSource::generateImpl()
 
     while (true)
     {
-        if (buffer->eof())
+        if (buffer->queueEmpty())
             break;
 
         auto new_rows = executor.execute();

src/Storages/RabbitMQ/ReadBufferFromRabbitMQConsumer.cpp

@@ -47,6 +47,12 @@ ReadBufferFromRabbitMQConsumer::~ReadBufferFromRabbitMQConsumer()
 }
 
 
+void ReadBufferFromRabbitMQConsumer::closeChannel()
+{
+    if (consumer_channel)
+        consumer_channel->close();
+}
+
 void ReadBufferFromRabbitMQConsumer::subscribe()
 {
     for (const auto & queue_name : queues)

src/Storages/RabbitMQ/ReadBufferFromRabbitMQConsumer.h

@@ -3,18 +3,24 @@
 #include <Core/Names.h>
 #include <base/types.h>
 #include <IO/ReadBuffer.h>
-#include <amqpcpp.h>
-#include <Storages/RabbitMQ/RabbitMQHandler.h>
 #include <Common/ConcurrentBoundedQueue.h>
 
 namespace Poco
 {
-    class Logger;
+class Logger;
+}
+
+namespace AMQP
+{
+class TcpChannel;
 }
 
 namespace DB
 {
 
+class RabbitMQHandler;
+using ChannelPtr = std::unique_ptr<AMQP::TcpChannel>;
+
 class ReadBufferFromRabbitMQConsumer : public ReadBuffer
 {
 
@@ -52,11 +58,7 @@ public:
     ChannelPtr & getChannel() { return consumer_channel; }
     void setupChannel();
     bool needChannelUpdate();
-    void closeChannel()
+    void closeChannel();
-    {
-        if (consumer_channel)
-            consumer_channel->close();
-    }
 
     void updateQueues(std::vector<String> & queues_) { queues = queues_; }
     size_t queuesCount() { return queues.size(); }

src/Storages/StorageMaterializedView.cpp

@@ -215,10 +215,10 @@ void StorageMaterializedView::drop()
     dropInnerTableIfAny(true, getContext());
 }
 
-void StorageMaterializedView::dropInnerTableIfAny(bool no_delay, ContextPtr local_context)
+void StorageMaterializedView::dropInnerTableIfAny(bool sync, ContextPtr local_context)
 {
     if (has_inner_table && tryGetTargetTable())
-        InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, target_table_id, no_delay);
+        InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, target_table_id, sync);
 }
 
 void StorageMaterializedView::truncate(const ASTPtr &, const StorageMetadataPtr &, ContextPtr local_context, TableExclusiveLockHolder &)

src/Storages/StorageMaterializedView.h

@@ -42,7 +42,7 @@ public:
     SinkToStoragePtr write(const ASTPtr & query, const StorageMetadataPtr & /*metadata_snapshot*/, ContextPtr context) override;
 
     void drop() override;
-    void dropInnerTableIfAny(bool no_delay, ContextPtr local_context) override;
+    void dropInnerTableIfAny(bool sync, ContextPtr local_context) override;
 
     void truncate(const ASTPtr &, const StorageMetadataPtr &, ContextPtr, TableExclusiveLockHolder &) override;
 

src/Storages/StorageReplicatedMergeTree.cpp

@@ -598,6 +598,9 @@ void StorageReplicatedMergeTree::createNewZooKeeperNodes()
     auto zookeeper = getZooKeeper();
 
     std::vector<zkutil::ZooKeeper::FutureCreate> futures;
+    /// We need to confirm /quorum exists here although it's called under createTableIfNotExists because in older CH releases (pre 22.4)
+    /// it was created here, so if metadata creation is done by an older replica the node might not exists when reaching this call
+    futures.push_back(zookeeper->asyncTryCreateNoThrow(zookeeper_path + "/quorum", String(), zkutil::CreateMode::Persistent));
     futures.push_back(zookeeper->asyncTryCreateNoThrow(zookeeper_path + "/quorum/parallel", String(), zkutil::CreateMode::Persistent));
 
     /// Nodes for remote fs zero-copy replication

src/Storages/WindowView/StorageWindowView.cpp

@@ -1606,7 +1606,7 @@ void StorageWindowView::drop()
     dropInnerTableIfAny(true, getContext());
 }
 
-void StorageWindowView::dropInnerTableIfAny(bool no_delay, ContextPtr local_context)
+void StorageWindowView::dropInnerTableIfAny(bool sync, ContextPtr local_context)
 {
     if (!std::exchange(has_inner_table, false))
         return;
@@ -1614,10 +1614,10 @@ void StorageWindowView::dropInnerTableIfAny(bool no_delay, ContextPtr local_cont
     try
     {
         InterpreterDropQuery::executeDropQuery(
-            ASTDropQuery::Kind::Drop, getContext(), local_context, inner_table_id, no_delay);
+            ASTDropQuery::Kind::Drop, getContext(), local_context, inner_table_id, sync);
 
         if (has_inner_target_table)
-            InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, target_table_id, no_delay);
+            InterpreterDropQuery::executeDropQuery(ASTDropQuery::Kind::Drop, getContext(), local_context, target_table_id, sync);
     }
     catch (...)
     {

src/Storages/WindowView/StorageWindowView.h

@@ -120,7 +120,7 @@ public:
 
     void checkTableCanBeDropped() const override;
 
-    void dropInnerTableIfAny(bool no_delay, ContextPtr context) override;
+    void dropInnerTableIfAny(bool sync, ContextPtr context) override;
 
     void drop() override;
 

tests/ci/integration_test_check.py

@@ -225,7 +225,7 @@ if __name__ == "__main__":
     output_path_log = os.path.join(result_path, "main_script_log.txt")
 
     runner_path = os.path.join(repo_path, "tests/integration", "ci-runner.py")
-    run_command = f"sudo -E {runner_path} | tee {output_path_log}"
+    run_command = f"sudo -E {runner_path}"
     logging.info("Going to run command: `%s`", run_command)
     logging.info(
         "ENV parameters for runner:\n%s",

tests/clickhouse-test

@@ -1490,9 +1490,9 @@ def collect_build_flags(args):
         result.append(BuildFlags.RELEASE)
 
     value = clickhouse_execute(
-        args, "SELECT value FROM system.settings WHERE name = 'default_database_engine'"
+        args, "SELECT value FROM system.settings WHERE name = 'allow_deprecated_database_ordinary'"
     )
-    if value == b"Ordinary":
+    if value == b"1":
         result.append(BuildFlags.ORDINARY_DATABASE)
 
     value = int(

tests/config/users.d/database_ordinary.xml

@@ -1,7 +1,7 @@
 <clickhouse>
     <profiles>
         <default>
-            <default_database_engine>Ordinary</default_database_engine>
+            <allow_deprecated_database_ordinary>1</allow_deprecated_database_ordinary>
         </default>
     </profiles>
 </clickhouse>