Support create a new table with CLONE AS

src/Interpreters/InterpreterCreateQuery.cpp

@@ -5,17 +5,19 @@
 #include <Access/AccessControl.h>
 #include <Access/User.h>
 
-#include <Common/Exception.h>
-#include <Common/StringUtils.h>
-#include <Common/escapeForFileName.h>
-#include <Common/typeid_cast.h>
-#include <Common/Macros.h>
-#include <Common/randomSeed.h>
-#include <Common/atomicRename.h>
-#include <Common/PoolId.h>
-#include <Common/logger_useful.h>
 #include <Core/Settings.h>
+#include <Interpreters/InterpreterAlterQuery.h>
+#include <Parsers/ASTPartition.h>
 #include <Parsers/ASTSetQuery.h>
+#include <Common/Exception.h>
+#include <Common/Macros.h>
+#include <Common/PoolId.h>
+#include <Common/StringUtils.h>
+#include <Common/atomicRename.h>
+#include <Common/escapeForFileName.h>
+#include <Common/logger_useful.h>
+#include <Common/randomSeed.h>
+#include <Common/typeid_cast.h>
 
 #include <Core/Defines.h>
 #include <Core/SettingsEnums.h>
@@ -826,6 +828,10 @@ InterpreterCreateQuery::TableProperties InterpreterCreateQuery::getTableProperti
         {
             /// Only MergeTree support TTL
             properties.columns.resetColumnTTLs();
+            if (create.is_clone_as)
+            {
+                throw Exception(ErrorCodes::SUPPORT_IS_DISABLED, "Only support 'CLONE AS' with tables of MergeTree family");
+            }
         }
 
         properties.constraints = as_storage_metadata->getConstraints();
@@ -1933,6 +1939,57 @@ BlockIO InterpreterCreateQuery::fillTableIfNeeded(const ASTCreateQuery & create)
             /* async_isnert */ false).execute();
     }
 
+    /// If the query is a CREATE .. CLONE AS <table>, insert the data into the table.
+    if (create.is_clone_as && !as_table_saved.empty() && !create.is_create_empty && !create.is_ordinary_view && !create.is_live_view
+        && (!(create.is_materialized_view || create.is_window_view) || create.is_populate))
+    {
+        String as_database_name = getContext()->resolveDatabase(create.as_database);
+        StorageID as_table_id = {as_database_name, as_table_saved};
+        StoragePtr as_table = DatabaseCatalog::instance().tryGetTable(as_table_id, getContext());
+        if (!as_table)
+        {
+            return {};
+        }
+
+        auto merge_tree_table = std::dynamic_pointer_cast<MergeTreeData>(as_table);
+        if (!merge_tree_table)
+        {
+            return {};
+        }
+
+        auto command_list = std::make_shared<ASTExpressionList>();
+        for (const auto & partition_id : merge_tree_table->getAllPartitionIds())
+        {
+            auto partition = std::make_shared<ASTPartition>();
+            partition->all = false;
+            partition->setPartitionID(std::make_shared<ASTLiteral>(partition_id));
+
+            auto command = std::make_shared<ASTAlterCommand>();
+            command->replace = false;
+
+            command->type = ASTAlterCommand::REPLACE_PARTITION;
+            command->partition = command->children.emplace_back(std::move(partition)).get();
+
+            command->from_database = as_database_name;
+            command->from_table = as_table_saved;
+
+            command->to_database = create.getDatabase();
+            command->to_table = create.getTable();
+
+            command_list->children.push_back(command);
+        }
+
+        auto query = std::make_shared<ASTAlterQuery>();
+        query->database = create.database;
+        query->table = create.table;
+        query->uuid = create.uuid;
+        auto * alter = query->as<ASTAlterQuery>();
+
+        alter->alter_object = ASTAlterQuery::AlterObjectType::TABLE;
+        alter->set(alter->command_list, command_list);
+        return InterpreterAlterQuery(query, getContext()).execute();
+    }
+
     return {};
 }
 

src/Parsers/ASTCreateQuery.cpp

@@ -425,9 +425,19 @@ void ASTCreateQuery::formatQueryImpl(const FormatSettings & settings, FormatStat
         settings.ostr << (settings.hilite ? hilite_keyword : "") << " EMPTY" << (settings.hilite ? hilite_none : "");
     };
 
+    bool should_add_clone = is_clone_as;
+    auto add_clone_if_needed = [&]
+    {
+        if (!should_add_clone)
+            return;
+        should_add_clone = false;
+        settings.ostr << (settings.hilite ? hilite_keyword : "") << " CLONE" << (settings.hilite ? hilite_none : "");
+    };
+
     if (!as_table.empty())
     {
         add_empty_if_needed();
+        add_clone_if_needed();
         settings.ostr
             << (settings.hilite ? hilite_keyword : "") << " AS " << (settings.hilite ? hilite_none : "")
             << (!as_database.empty() ? backQuoteIfNeed(as_database) + "." : "") << backQuoteIfNeed(as_table);
@@ -446,6 +456,7 @@ void ASTCreateQuery::formatQueryImpl(const FormatSettings & settings, FormatStat
         }
 
         add_empty_if_needed();
+        add_clone_if_needed();
         settings.ostr << (settings.hilite ? hilite_keyword : "") << " AS " << (settings.hilite ? hilite_none : "");
         as_table_function->formatImpl(settings, state, frame);
     }

src/Parsers/ASTCreateQuery.h

@@ -100,6 +100,7 @@ public:
     bool is_time_series_table{false}; /// CREATE TABLE ... ENGINE=TimeSeries() ...
     bool is_populate{false};
     bool is_create_empty{false};    /// CREATE TABLE ... EMPTY AS SELECT ...
+    bool is_clone_as{false};    /// CREATE TABLE ... CLONE AS ...
     bool replace_view{false}; /// CREATE OR REPLACE VIEW
     bool has_uuid{false}; // CREATE TABLE x UUID '...'
 

src/Parsers/CommonParsers.h

@@ -84,6 +84,7 @@ namespace DB
     MR_MACROS(CLEAR_INDEX, "CLEAR INDEX") \
     MR_MACROS(CLEAR_PROJECTION, "CLEAR PROJECTION") \
     MR_MACROS(CLEAR_STATISTICS, "CLEAR STATISTICS") \
+    MR_MACROS(CLONE_AS, "CLONE AS") \
     MR_MACROS(CLUSTER, "CLUSTER") \
     MR_MACROS(CLUSTERS, "CLUSTERS") \
     MR_MACROS(CN, "CN") \

src/Parsers/ParserCreateQuery.cpp

@@ -675,6 +675,7 @@ bool ParserCreateTableQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expe
     bool if_not_exists = false;
     bool is_temporary = false;
     bool is_create_empty = false;
+    bool is_clone_as = false;
 
     if (s_create.ignore(pos, expected))
     {
@@ -759,13 +760,18 @@ bool ParserCreateTableQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expe
         return true;
     };
 
-    auto need_parse_as_select = [&is_create_empty, &pos, &expected]()
+    auto need_parse_as_select = [&is_create_empty, &is_clone_as, &pos, &expected]()
     {
         if (ParserKeyword{Keyword::EMPTY_AS}.ignore(pos, expected))
         {
             is_create_empty = true;
             return true;
         }
+        if (ParserKeyword{Keyword::CLONE_AS}.ignore(pos, expected))
+        {
+            is_clone_as = true;
+            return true;
+        }
 
         return ParserKeyword{Keyword::AS}.ignore(pos, expected);
     };
@@ -893,6 +899,7 @@ bool ParserCreateTableQuery::parseImpl(Pos & pos, ASTPtr & node, Expected & expe
     query->set(query->select, select);
     query->set(query->targets, targets);
     query->is_create_empty = is_create_empty;
+    query->is_clone_as = is_clone_as;
 
     if (from_path)
         query->attach_from_path = from_path->as<ASTLiteral &>().value.safeGet<String>();