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place optimizeIf() after scalar subqueries + better getTablesWithColumns()

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This commit is contained in:
Artem Zuikov 2020-02-27 17:33:03 +03:00
parent db502ecd74
commit 2c09017a33
2 changed files with 74 additions and 60 deletions
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132
dbms/src/Interpreters/SyntaxAnalyzer.cpp
View File

@ -118,6 +118,41 @@ std::vector<TableWithColumnNames> getTablesWithColumns(const std::vector<const A
return tables_with_columns;
}
std::vector<TableWithColumnNames> getTablesWithColumns(const ASTSelectQuery & select_query, StoragePtr storage, const Context & context,
const NamesAndTypesList & source_columns,
NamesAndTypesList & columns_from_joined_table)
{
std::vector<TableWithColumnNames> tables_with_columns;
std::vector<const ASTTableExpression *> table_expressions = getTableExpressions(select_query);
tables_with_columns = getTablesWithColumns(table_expressions, context);
if (tables_with_columns.empty())
{
if (storage)
{
const ColumnsDescription & storage_columns = storage->getColumns();
tables_with_columns.emplace_back(DatabaseAndTableWithAlias{}, storage_columns.getOrdinary().getNames());
auto & table = tables_with_columns.back();
table.addHiddenColumns(storage_columns.getMaterialized());
table.addHiddenColumns(storage_columns.getAliases());
table.addHiddenColumns(storage_columns.getVirtuals());
}
else
{
Names columns;
columns.reserve(source_columns.size());
for (const auto & column : source_columns)
columns.push_back(column.name);
tables_with_columns.emplace_back(DatabaseAndTableWithAlias{}, columns);
}
}
if (table_expressions.size() > 1)
columns_from_joined_table = getColumnsFromTableExpression(*table_expressions[1], context);
return tables_with_columns;
}
/// Translate qualified names such as db.table.column, table.column, table_alias.column to names' normal form.
/// Expand asterisks and qualified asterisks with column names.
@ -462,6 +497,15 @@ void optimizeUsing(const ASTSelectQuery * select_query)
expression_list = uniq_expressions_list;
}
void optimizeIf(ASTPtr & query, Aliases & aliases, bool if_chain_to_miltiif)
{
/// Optimize if with constant condition after constants was substituted instead of scalar subqueries.
OptimizeIfWithConstantConditionVisitor(aliases).visit(query);
if (if_chain_to_miltiif)
OptimizeIfChainsVisitor().visit(query);
}
void getArrayJoinedColumns(ASTPtr & query, SyntaxAnalyzerResult & result, const ASTSelectQuery * select_query,
const NamesAndTypesList & source_columns, const NameSet & source_columns_set)
{
@ -800,7 +844,6 @@ void SyntaxAnalyzerResult::collectUsedColumns(const ASTPtr & query, const NamesA
required_source_columns.swap(source_columns);
}
SyntaxAnalyzerResultPtr SyntaxAnalyzer::analyzeSelect(
ASTPtr & query,
const NamesAndTypesList & source_columns,
@ -831,60 +874,33 @@ SyntaxAnalyzerResultPtr SyntaxAnalyzer::analyzeSelect(
if (storage)
collectSourceColumns(storage->getColumns(), result.source_columns, true);
NameSet source_columns_set = removeDuplicateColumns(result.source_columns);
std::vector<TableWithColumnNames> tables_with_columns;
if (remove_duplicates)
renameDuplicatedColumns(select_query);
if (settings.enable_optimize_predicate_expression)
if (const ASTTablesInSelectQueryElement * table_join_node = select_query->join())
replaceJoinedTable(table_join_node);
NamesAndTypesList & columns_from_joined_table = result.analyzed_join->columns_from_joined_table;
std::vector<TableWithColumnNames> tables_with_columns =
getTablesWithColumns(*select_query, storage, context, result.source_columns, columns_from_joined_table);
if (columns_from_joined_table.size())
{
if (remove_duplicates)
renameDuplicatedColumns(select_query);
const ASTTablesInSelectQueryElement * table_join_node = select_query->join();
if (table_join_node)
{
if (settings.enable_optimize_predicate_expression)
replaceJoinedTable(table_join_node);
}
std::vector<const ASTTableExpression *> table_expressions = getTableExpressions(*select_query);
tables_with_columns = getTablesWithColumns(table_expressions, context);
if (tables_with_columns.empty())
{
if (storage)
{
const ColumnsDescription & storage_columns = storage->getColumns();
tables_with_columns.emplace_back(DatabaseAndTableWithAlias{}, storage_columns.getOrdinary().getNames());
auto & table = tables_with_columns.back();
table.addHiddenColumns(storage_columns.getMaterialized());
table.addHiddenColumns(storage_columns.getAliases());
table.addHiddenColumns(storage_columns.getVirtuals());
}
else
{
Names columns;
columns.reserve(result.source_columns.size());
for (const auto & column : result.source_columns)
columns.push_back(column.name);
tables_with_columns.emplace_back(DatabaseAndTableWithAlias{}, columns);
}
}
if (table_expressions.size() > 1)
{
result.analyzed_join->columns_from_joined_table = getColumnsFromTableExpression(*table_expressions[1], context);
result.analyzed_join->deduplicateAndQualifyColumnNames(
source_columns_set, tables_with_columns[1].table.getQualifiedNamePrefix());
}
translateQualifiedNames(query, *select_query, source_columns_set, tables_with_columns);
/// Rewrite IN and/or JOIN for distributed tables according to distributed_product_mode setting.
InJoinSubqueriesPreprocessor(context).visit(query);
/// Optimizes logical expressions.
LogicalExpressionsOptimizer(select_query, settings.optimize_min_equality_disjunction_chain_length.value).perform();
result.analyzed_join->deduplicateAndQualifyColumnNames(
source_columns_set, tables_with_columns[1].table.getQualifiedNamePrefix());
}
rewriteAst(query, settings, result.aliases);
translateQualifiedNames(query, *select_query, source_columns_set, tables_with_columns);
/// Rewrite IN and/or JOIN for distributed tables according to distributed_product_mode setting.
InJoinSubqueriesPreprocessor(context).visit(query);
/// Optimizes logical expressions.
LogicalExpressionsOptimizer(select_query, settings.optimize_min_equality_disjunction_chain_length.value).perform();
normalize(query, settings, result.aliases);
/// Remove unneeded columns according to 'required_result_columns'.
/// Leave all selected columns in case of DISTINCT; columns that contain arrayJoin function inside.
@ -896,6 +912,8 @@ SyntaxAnalyzerResultPtr SyntaxAnalyzer::analyzeSelect(
executeScalarSubqueries(query, context, subquery_depth, result.scalars);
{
optimizeIf(query, result.aliases, settings.optimize_if_chain_to_miltiif);
/// Push the predicate expression down to the subqueries.
result.rewrite_subqueries = PredicateExpressionsOptimizer(context, tables_with_columns, settings).optimize(*select_query);
@ -939,17 +957,19 @@ SyntaxAnalyzerResultPtr SyntaxAnalyzer::analyze(ASTPtr & query, const NamesAndTy
collectSourceColumns(storage->getColumns(), result.source_columns, false);
removeDuplicateColumns(result.source_columns);
rewriteAst(query, settings, result.aliases);
normalize(query, settings, result.aliases);
/// Executing scalar subqueries. Column defaults could be a scalar subquery.
executeScalarSubqueries(query, context, 0, result.scalars);
optimizeIf(query, result.aliases, settings.optimize_if_chain_to_miltiif);
result.aggregates = getAggregates(query);
result.collectUsedColumns(query, {});
return std::make_shared<const SyntaxAnalyzerResult>(result);
}
void SyntaxAnalyzer::rewriteAst(ASTPtr & query, const Settings & settings, Aliases & aliases) const
void SyntaxAnalyzer::normalize(ASTPtr & query, const Settings & settings, Aliases & aliases) const
{
CustomizeFunctionsVisitor::Data data{settings.count_distinct_implementation};
CustomizeFunctionsVisitor(data).visit(query);
@ -965,12 +985,6 @@ void SyntaxAnalyzer::rewriteAst(ASTPtr & query, const Settings & settings, Alias
/// Common subexpression elimination. Rewrite rules.
QueryNormalizer::Data normalizer_data(aliases, settings);
QueryNormalizer(normalizer_data).visit(query);
/// Optimize if with constant condition after constants was substituted instead of scalar subqueries.
OptimizeIfWithConstantConditionVisitor(aliases).visit(query);
if (settings.optimize_if_chain_to_miltiif)
OptimizeIfChainsVisitor().visit(query);
}
}

2
dbms/src/Interpreters/SyntaxAnalyzer.h
View File

@ -89,7 +89,7 @@ public:
private:
const Context & context;
void rewriteAst(ASTPtr & query, const Settings & settings, Aliases & aliases) const;
void normalize(ASTPtr & query, const Settings & settings, Aliases & aliases) const;
};
}