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add ColumnAliasesVisitor to improve partition prune for mergetree
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50
src/Interpreters/ColumnAliasesVisitor.cpp
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50
src/Interpreters/ColumnAliasesVisitor.cpp
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@ -0,0 +1,50 @@
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#include <Interpreters/ColumnAliasesVisitor.h>
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#include <Interpreters/IdentifierSemantic.h>
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#include <Interpreters/addTypeConversionToAST.h>
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#include <Parsers/ASTTablesInSelectQuery.h>
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#include <Parsers/ASTSelectWithUnionQuery.h>
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#include <Parsers/ASTSelectQuery.h>
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#include <Parsers/ASTSubquery.h>
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#include <Parsers/ASTAlterQuery.h>
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#include <Parsers/ASTInsertQuery.h>
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#include <Parsers/ASTIdentifier.h>
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namespace DB
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{
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bool ColumnAliasesMatcher::needChildVisit(const ASTPtr & node, const ASTPtr &)
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{
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return !(node->as<ASTTableExpression>()
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|| node->as<ASTSubquery>()
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|| node->as<ASTArrayJoin>()
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|| node->as<ASTSelectWithUnionQuery>());
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}
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void ColumnAliasesMatcher::visit(ASTPtr & ast, Data & data)
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{
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if (auto * node = ast->as<ASTIdentifier>())
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{
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if (auto column_name = IdentifierSemantic::getColumnName(*node))
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{
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if (const auto column_default = data.columns.getDefault(column_name.value()))
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{
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if (column_default.value().kind == ColumnDefaultKind::Alias)
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{
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const auto alias_columns = data.columns.getAliases();
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for (const auto & alias_column : alias_columns)
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{
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if (alias_column.name == column_name.value())
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{
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ast = addTypeConversionToAST(column_default.value().expression->clone(), alias_column.type->getName());
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//revisit ast to track recursive alias columns
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Visitor(data).visit(ast);
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break;
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}
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}
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}
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}
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}
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}
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}
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}
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37
src/Interpreters/ColumnAliasesVisitor.h
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37
src/Interpreters/ColumnAliasesVisitor.h
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@ -0,0 +1,37 @@
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#pragma once
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#include <Interpreters/Aliases.h>
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#include <Interpreters/InDepthNodeVisitor.h>
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#include <Storages/ColumnsDescription.h>
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namespace DB
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{
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class IAST;
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using ASTPtr = std::shared_ptr<IAST>;
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class IDataType;
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using DataTypePtr = std::shared_ptr<const IDataType>;
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/// Visits AST node to rewrite alias columns in filter query
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/// Currently works only in `KeyCondition` of select query
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class ColumnAliasesMatcher
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{
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public:
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using Visitor = InDepthNodeVisitor<ColumnAliasesMatcher, false>;
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struct Data
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{
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const ColumnsDescription & columns;
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Data(const ColumnsDescription & columns_)
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: columns(columns_)
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{}
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};
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static void visit(ASTPtr & ast, Data & data);
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static bool needChildVisit(const ASTPtr & node, const ASTPtr & child);
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};
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using ColumnAliasesVisitor = ColumnAliasesMatcher::Visitor;
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}
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@ -30,6 +30,7 @@
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#include <Interpreters/JoinSwitcher.h>
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#include <Interpreters/JoinedTables.h>
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#include <Interpreters/QueryAliasesVisitor.h>
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#include <Interpreters/ColumnAliasesVisitor.h>
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#include <Processors/Pipe.h>
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#include <Processors/Sources/SourceFromInputStream.h>
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@ -1291,8 +1292,11 @@ void InterpreterSelectQuery::executeFetchColumns(
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{
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auto column_decl = storage_columns.get(column);
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/// TODO: can make CAST only if the type is different (but requires SyntaxAnalyzer).
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auto cast_column_default = addTypeConversionToAST(column_default->expression->clone(), column_decl.type->getName());
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column_expr = setAlias(cast_column_default->clone(), column);
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column_expr = addTypeConversionToAST(column_default->expression->clone(), column_decl.type->getName());
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// recursive visit for alias to alias
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ColumnAliasesVisitor::Data data(storage_columns);
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ColumnAliasesVisitor(data).visit(column_expr);
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column_expr = setAlias(column_expr, column);
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}
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else
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column_expr = std::make_shared<ASTIdentifier>(column);
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@ -34,6 +34,7 @@ SRCS(
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ClusterProxy/SelectStreamFactory.cpp
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ClusterProxy/executeQuery.cpp
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CollectJoinOnKeysVisitor.cpp
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ColumnAliasesVisitor.cpp
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Context.cpp
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CrashLog.cpp
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CrossToInnerJoinVisitor.cpp
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@ -13,6 +13,7 @@
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#include <Common/typeid_cast.h>
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#include <Interpreters/convertFieldToType.h>
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#include <Interpreters/Set.h>
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#include <Interpreters/ColumnAliasesVisitor.h>
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#include <Parsers/queryToString.h>
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#include <Parsers/ASTLiteral.h>
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#include <Parsers/ASTSubquery.h>
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@ -371,11 +372,12 @@ Block KeyCondition::getBlockWithConstants(
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KeyCondition::KeyCondition(
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const SelectQueryInfo & query_info,
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const Context & context,
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const ColumnsDescription & columns_desc_,
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const Names & key_column_names,
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const ExpressionActionsPtr & key_expr_,
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bool single_point_,
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bool strict_)
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: key_expr(key_expr_), prepared_sets(query_info.sets), single_point(single_point_), strict(strict_)
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: key_expr(key_expr_), prepared_sets(query_info.sets), columns_desc(columns_desc_), single_point(single_point_), strict(strict_)
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{
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for (size_t i = 0, size = key_column_names.size(); i < size; ++i)
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{
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@ -405,7 +407,12 @@ KeyCondition::KeyCondition(
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* To overcome the problem, before parsing the AST we transform it to its semantically equivalent form where all NOT's
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* are pushed down and applied (when possible) to leaf nodes.
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*/
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traverseAST(cloneASTWithInversionPushDown(filter_query), context, block_with_constants);
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auto cloned_query = cloneASTWithInversionPushDown(filter_query);
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ColumnAliasesVisitor::Data data{columns_desc};
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ColumnAliasesVisitor(data).visit(cloned_query);
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traverseAST(cloned_query, context, block_with_constants);
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}
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else
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{
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@ -8,6 +8,7 @@
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#include <Parsers/ASTSelectQuery.h>
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#include <Parsers/ASTFunction.h>
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#include <Storages/SelectQueryInfo.h>
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#include <Storages/ColumnsDescription.h>
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namespace DB
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@ -230,6 +231,7 @@ public:
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KeyCondition(
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const SelectQueryInfo & query_info,
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const Context & context,
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const ColumnsDescription & columns_desc_,
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const Names & key_column_names,
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const ExpressionActionsPtr & key_expr,
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bool single_point_ = false,
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@ -418,6 +420,7 @@ private:
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ColumnIndices key_columns;
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ExpressionActionsPtr key_expr;
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PreparedSets prepared_sets;
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const ColumnsDescription & columns_desc;
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// If true, always allow key_expr to be wrapped by function
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bool single_point;
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@ -209,7 +209,7 @@ QueryPlanPtr MergeTreeDataSelectExecutor::readFromParts(
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const auto & primary_key = metadata_snapshot->getPrimaryKey();
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Names primary_key_columns = primary_key.column_names;
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KeyCondition key_condition(query_info, context, primary_key_columns, primary_key.expression);
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KeyCondition key_condition(query_info, context, metadata_snapshot->getColumns(), primary_key_columns, primary_key.expression);
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if (settings.force_primary_key && key_condition.alwaysUnknownOrTrue())
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{
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@ -221,8 +221,8 @@ QueryPlanPtr MergeTreeDataSelectExecutor::readFromParts(
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std::optional<PartitionPruner> partition_pruner;
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if (data.minmax_idx_expr)
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{
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minmax_idx_condition.emplace(query_info, context, data.minmax_idx_columns, data.minmax_idx_expr);
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partition_pruner.emplace(metadata_snapshot->getPartitionKey(), query_info, context, false /* strict */);
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minmax_idx_condition.emplace(query_info, context, metadata_snapshot->getColumns(), data.minmax_idx_columns, data.minmax_idx_expr);
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partition_pruner.emplace(metadata_snapshot->getPartitionKey(), metadata_snapshot->getColumns(), query_info, context, false /* strict */);
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if (settings.force_index_by_date && (minmax_idx_condition->alwaysUnknownOrTrue() && partition_pruner->isUseless()))
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{
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@ -559,7 +559,7 @@ QueryPlanPtr MergeTreeDataSelectExecutor::readFromParts(
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for (const auto & index : metadata_snapshot->getSecondaryIndices())
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{
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auto index_helper = MergeTreeIndexFactory::instance().get(index);
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auto condition = index_helper->createIndexCondition(query_info, context);
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auto condition = index_helper->createIndexCondition(query_info, metadata_snapshot->getColumns(), context);
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if (!condition->alwaysUnknownOrTrue())
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useful_indices.emplace_back(index_helper, condition);
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}
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@ -67,7 +67,7 @@ MergeTreeIndexAggregatorPtr MergeTreeIndexBloomFilter::createIndexAggregator() c
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return std::make_shared<MergeTreeIndexAggregatorBloomFilter>(bits_per_row, hash_functions, index.column_names);
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}
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MergeTreeIndexConditionPtr MergeTreeIndexBloomFilter::createIndexCondition(const SelectQueryInfo & query_info, const Context & context) const
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MergeTreeIndexConditionPtr MergeTreeIndexBloomFilter::createIndexCondition(const SelectQueryInfo & query_info, const ColumnsDescription & /*columns*/, const Context & context) const
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{
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return std::make_shared<MergeTreeIndexConditionBloomFilter>(query_info, context, index.sample_block, hash_functions);
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}
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@ -20,7 +20,7 @@ public:
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MergeTreeIndexAggregatorPtr createIndexAggregator() const override;
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MergeTreeIndexConditionPtr createIndexCondition(const SelectQueryInfo & query_info, const Context & context) const override;
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MergeTreeIndexConditionPtr createIndexCondition(const SelectQueryInfo & query_info, const ColumnsDescription & columns, const Context & context) const override;
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bool mayBenefitFromIndexForIn(const ASTPtr & node) const override;
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@ -562,7 +562,7 @@ MergeTreeIndexAggregatorPtr MergeTreeIndexFullText::createIndexAggregator() cons
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}
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MergeTreeIndexConditionPtr MergeTreeIndexFullText::createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const
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const SelectQueryInfo & query, const ColumnsDescription & /*columns*/, const Context & context) const
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{
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return std::make_shared<MergeTreeConditionFullText>(query, context, index.sample_block, params, token_extractor.get());
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};
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@ -199,7 +199,7 @@ public:
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MergeTreeIndexAggregatorPtr createIndexAggregator() const override;
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MergeTreeIndexConditionPtr createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const override;
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const SelectQueryInfo & query, const ColumnsDescription & columns, const Context & context) const override;
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bool mayBenefitFromIndexForIn(const ASTPtr & node) const override;
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@ -132,9 +132,10 @@ void MergeTreeIndexAggregatorMinMax::update(const Block & block, size_t * pos, s
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MergeTreeIndexConditionMinMax::MergeTreeIndexConditionMinMax(
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const IndexDescription & index,
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const SelectQueryInfo & query,
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const ColumnsDescription & columns,
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const Context & context)
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: index_data_types(index.data_types)
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, condition(query, context, index.column_names, index.expression)
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, condition(query, context, columns, index.column_names, index.expression)
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{
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}
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@ -169,9 +170,9 @@ MergeTreeIndexAggregatorPtr MergeTreeIndexMinMax::createIndexAggregator() const
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}
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MergeTreeIndexConditionPtr MergeTreeIndexMinMax::createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const
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const SelectQueryInfo & query, const ColumnsDescription & columns, const Context & context) const
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{
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return std::make_shared<MergeTreeIndexConditionMinMax>(index, query, context);
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return std::make_shared<MergeTreeIndexConditionMinMax>(index, query, columns, context);
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};
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bool MergeTreeIndexMinMax::mayBenefitFromIndexForIn(const ASTPtr & node) const
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@ -52,6 +52,7 @@ public:
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MergeTreeIndexConditionMinMax(
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const IndexDescription & index,
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const SelectQueryInfo & query,
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const ColumnsDescription & columns,
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const Context & context);
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bool alwaysUnknownOrTrue() const override;
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@ -78,7 +79,7 @@ public:
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MergeTreeIndexAggregatorPtr createIndexAggregator() const override;
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MergeTreeIndexConditionPtr createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const override;
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const SelectQueryInfo & query, const ColumnsDescription & columns, const Context & context) const override;
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bool mayBenefitFromIndexForIn(const ASTPtr & node) const override;
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};
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@ -468,7 +468,7 @@ MergeTreeIndexAggregatorPtr MergeTreeIndexSet::createIndexAggregator() const
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}
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MergeTreeIndexConditionPtr MergeTreeIndexSet::createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const
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const SelectQueryInfo & query, const ColumnsDescription & /*columns*/, const Context & context) const
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{
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return std::make_shared<MergeTreeIndexConditionSet>(index.name, index.sample_block, max_rows, query, context);
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};
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@ -129,7 +129,7 @@ public:
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MergeTreeIndexAggregatorPtr createIndexAggregator() const override;
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MergeTreeIndexConditionPtr createIndexCondition(
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const SelectQueryInfo & query, const Context & context) const override;
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const SelectQueryInfo & query, const ColumnsDescription & columns, const Context & context) const override;
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bool mayBenefitFromIndexForIn(const ASTPtr & node) const override;
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@ -85,7 +85,7 @@ struct IMergeTreeIndex
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virtual MergeTreeIndexAggregatorPtr createIndexAggregator() const = 0;
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virtual MergeTreeIndexConditionPtr createIndexCondition(
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const SelectQueryInfo & query_info, const Context & context) const = 0;
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const SelectQueryInfo & query_info, const ColumnsDescription & columns, const Context & context) const = 0;
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Names getColumnsRequiredForIndexCalc() const { return index.expression->getRequiredColumns(); }
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@ -3,6 +3,7 @@
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#include <unordered_map>
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#include <Storages/KeyDescription.h>
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#include <Storages/ColumnsDescription.h>
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#include <Storages/MergeTree/IMergeTreeDataPart.h>
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#include <Storages/MergeTree/KeyCondition.h>
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@ -21,10 +22,10 @@ private:
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using DataPartPtr = std::shared_ptr<const DataPart>;
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public:
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PartitionPruner(const KeyDescription & partition_key_, const SelectQueryInfo & query_info, const Context & context, bool strict)
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PartitionPruner(const KeyDescription & partition_key_, const ColumnsDescription & columns, const SelectQueryInfo & query_info, const Context & context, bool strict)
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: partition_key(partition_key_)
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, partition_condition(
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query_info, context, partition_key.column_names, partition_key.expression, true /* single_point */, strict)
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query_info, context, columns, partition_key.column_names, partition_key.expression, true /* single_point */, strict)
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, useless(partition_condition.alwaysUnknownOrTrue())
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{
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}
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@ -210,7 +210,7 @@ std::optional<UInt64> StorageMergeTree::totalRows() const
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std::optional<UInt64> StorageMergeTree::totalRowsByPartitionPredicate(const SelectQueryInfo & query_info, const Context & context) const
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{
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auto metadata_snapshot = getInMemoryMetadataPtr();
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PartitionPruner partition_pruner(metadata_snapshot->getPartitionKey(), query_info, context, true /* strict */);
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PartitionPruner partition_pruner(metadata_snapshot->getPartitionKey(), metadata_snapshot->getColumns(), query_info, context, true /* strict */);
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if (partition_pruner.isUseless())
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return {};
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size_t res = 0;
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@ -3730,7 +3730,7 @@ std::optional<UInt64> StorageReplicatedMergeTree::totalRows() const
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std::optional<UInt64> StorageReplicatedMergeTree::totalRowsByPartitionPredicate(const SelectQueryInfo & query_info, const Context & context) const
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{
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auto metadata_snapshot = getInMemoryMetadataPtr();
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PartitionPruner partition_pruner(metadata_snapshot->getPartitionKey(), query_info, context, true /* strict */);
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PartitionPruner partition_pruner(metadata_snapshot->getPartitionKey(), metadata_snapshot->getColumns(), query_info, context, true /* strict */);
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if (partition_pruner.isUseless())
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return {};
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size_t res = 0;
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@ -0,0 +1,17 @@
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test-partition-prune
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1
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1
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1
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1
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1
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test-join
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1
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1
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alias2alias
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1
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1
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1
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1
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1
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1
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1
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70
tests/queries/0_stateless/01576_alias_column_rewrite.sql
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70
tests/queries/0_stateless/01576_alias_column_rewrite.sql
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DROP TABLE IF EXISTS table_with_alias_column;
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CREATE TABLE table_with_alias_column
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(
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`timestamp` DateTime,
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`value` UInt64,
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`day` Date ALIAS toDate(timestamp),
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`day1` Date ALIAS day + 1,
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`day2` Date ALIAS day1 + 1,
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`time` DateTime ALIAS timestamp
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)
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ENGINE = MergeTree
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PARTITION BY toYYYYMMDD(timestamp)
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ORDER BY timestamp;
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INSERT INTO table_with_alias_column(timestamp, value) SELECT toDateTime('2020-01-01 12:00:00'), 1 FROM numbers(1000);
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INSERT INTO table_with_alias_column(timestamp, value) SELECT toDateTime('2020-01-02 12:00:00'), 1 FROM numbers(1000);
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INSERT INTO table_with_alias_column(timestamp, value) SELECT toDateTime('2020-01-03 12:00:00'), 1 FROM numbers(1000);
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SELECT 'test-partition-prune';
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SELECT COUNT() = 1000 FROM table_with_alias_column WHERE day = '2020-01-01' SETTINGS max_rows_to_read = 1000;
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SELECT t = '2020-01-03' FROM (SELECT day as t FROM table_with_alias_column WHERE t = '2020-01-03' GROUP BY t SETTINGS max_rows_to_read = 1000);
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SELECT COUNT() = 1000 FROM table_with_alias_column WHERE day = '2020-01-01' UNION ALL select 1 from numbers(1) SETTINGS max_rows_to_read = 1001;
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SELECT COUNT() = 0 FROM (SELECT toDate('2019-01-01') as day, day as t FROM table_with_alias_column PREWHERE t = '2020-01-03' WHERE t = '2020-01-03' GROUP BY t );
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SELECT 'test-join';
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SELECT day = '2020-01-03'
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FROM
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(
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SELECT toDate('2020-01-03') AS day
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FROM numbers(1)
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) AS a
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INNER JOIN
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(
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SELECT day
|
||||
FROM table_with_alias_column
|
||||
WHERE day = '2020-01-03'
|
||||
GROUP BY day SETTINGS max_rows_to_read = 1000
|
||||
) AS b ON a.day = b.day;
|
||||
|
||||
SELECT day = '2020-01-01'
|
||||
FROM
|
||||
(
|
||||
SELECT day
|
||||
FROM table_with_alias_column
|
||||
WHERE day = '2020-01-01'
|
||||
GROUP BY day SETTINGS max_rows_to_read = 1001
|
||||
) AS a
|
||||
INNER JOIN
|
||||
(
|
||||
SELECT toDate('2020-01-01') AS day
|
||||
FROM numbers(1)
|
||||
) AS b ON a.day = b.day;
|
||||
|
||||
|
||||
SELECT 'alias2alias';
|
||||
SELECT COUNT() = 1000 FROM table_with_alias_column WHERE day1 = '2020-01-02' SETTINGS max_rows_to_read = 1000;
|
||||
SELECT t = '2020-01-03' FROM (SELECT day1 as t FROM table_with_alias_column WHERE t = '2020-01-03' GROUP BY t SETTINGS max_rows_to_read = 1000);
|
||||
SELECT t = '2020-01-03' FROM (SELECT day2 as t FROM table_with_alias_column WHERE t = '2020-01-03' GROUP BY t SETTINGS max_rows_to_read = 1000);
|
||||
SELECT COUNT() = 1000 FROM table_with_alias_column WHERE day1 = '2020-01-03' UNION ALL select 1 from numbers(1) SETTINGS max_rows_to_read = 1001;
|
||||
SELECT COUNT() = 0 FROM (SELECT toDate('2019-01-01') as day1, day1 as t FROM table_with_alias_column PREWHERE t = '2020-01-03' WHERE t = '2020-01-03' GROUP BY t );
|
||||
SELECT day1 = '2020-01-04' FROM table_with_alias_column PREWHERE day1 = '2020-01-04' WHERE day1 = '2020-01-04' GROUP BY day1 SETTINGS max_rows_to_read = 1000;
|
||||
|
||||
DROP TABLE table_with_alias_column;
|
||||
|
Loading…
Reference in New Issue
Block a user