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Merge pull request #2881 from zhang2014/feature/support_optimize_predicate_for_view

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ISSUES-863 support optimize predicate for view
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alexey-milovidov 2018-09-08 00:43:13 +03:00 committed by GitHub
commit ef22af2e49
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4 changed files with 45 additions and 2 deletions
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37
dbms/src/Storages/StorageView.cpp
View File

@ -1,11 +1,14 @@
#include <Interpreters/InterpreterSelectQuery.h>
#include <Interpreters/InterpreterSelectWithUnionQuery.h>
#include <Parsers/ASTCreateQuery.h>
#include <Parsers/ASTSubquery.h>
#include <Storages/StorageView.h>
#include <Storages/StorageFactory.h>
#include <DataStreams/MaterializingBlockInputStream.h>
#include <Common/typeid_cast.h>
namespace DB
{
@ -13,6 +16,7 @@ namespace DB
namespace ErrorCodes
{
extern const int INCORRECT_QUERY;
extern const int LOGICAL_ERROR;
}
@ -31,14 +35,26 @@ StorageView::StorageView(
BlockInputStreams StorageView::read(
const Names & column_names,
const SelectQueryInfo & /*query_info*/,
const SelectQueryInfo & query_info,
const Context & context,
QueryProcessingStage::Enum processed_stage,
const size_t /*max_block_size*/,
const unsigned /*num_streams*/)
{
checkQueryProcessingStage(processed_stage, context);
BlockInputStreams res = InterpreterSelectWithUnionQuery(inner_query, context, column_names).executeWithMultipleStreams();
BlockInputStreams res;
if (context.getSettings().enable_optimize_predicate_expression)
{
replaceTableNameWithSubquery(typeid_cast<ASTSelectQuery *>(query_info.query.get()), inner_query);
auto res_io = InterpreterSelectQuery(query_info.query, context, column_names, processed_stage).execute();
res.emplace_back(res_io.in);
return res;
}
res = InterpreterSelectWithUnionQuery(inner_query, context, column_names).executeWithMultipleStreams();
/// It's expected that the columns read from storage are not constant.
/// Because method 'getSampleBlockForColumns' is used to obtain a structure of result in InterpreterSelectQuery.
@ -48,6 +64,23 @@ BlockInputStreams StorageView::read(
return res;
}
void StorageView::replaceTableNameWithSubquery(ASTSelectQuery * select_query, ASTPtr & subquery)
{
ASTTablesInSelectQueryElement * select_element = static_cast<ASTTablesInSelectQueryElement *>(select_query->tables->children[0].get());
if (!select_element->table_expression)
throw Exception("Logical error: incorrect table expression", ErrorCodes::LOGICAL_ERROR);
ASTTableExpression * table_expression = static_cast<ASTTableExpression *>(select_element->table_expression.get());
if (!table_expression->database_and_table_name)
throw Exception("Logical error: incorrect table expression", ErrorCodes::LOGICAL_ERROR);
table_expression->database_and_table_name = {};
table_expression->subquery = std::make_shared<ASTSubquery>();
table_expression->subquery->children.push_back(subquery->clone());
}
void registerStorageView(StorageFactory & factory)
{

3
dbms/src/Storages/StorageView.h
View File

@ -2,6 +2,7 @@
#include <ext/shared_ptr_helper.h>
#include <Storages/IStorage.h>
#include <Parsers/ASTSelectQuery.h>
namespace DB
@ -38,6 +39,8 @@ private:
String table_name;
ASTPtr inner_query;
void replaceTableNameWithSubquery(ASTSelectQuery * select_query, ASTPtr & subquery);
protected:
StorageView(
const String & table_name_,

1
dbms/tests/queries/0_stateless/00597_push_down_predicate.reference
View File

@ -20,5 +20,6 @@
2000-01-01 1 test string 1 1 2000-01-01 1 test string 1 1
2000-01-01 1 test string 1 1
1 2000-01-01 2000-01-01 1 test string 1 1
2000-01-01 1 test string 1 1
-------Push to having expression, need check.-------
-------Compatibility test-------

6
dbms/tests/queries/0_stateless/00597_push_down_predicate.sql
View File

@ -1,8 +1,10 @@
SET send_logs_level = 'none';
DROP TABLE IF EXISTS test.test;
DROP TABLE IF EXISTS test.test_view;
CREATE TABLE test.test(date Date, id Int8, name String, value Int64) ENGINE = MergeTree(date, (id, date), 8192);
CREATE VIEW test.test_view AS SELECT * FROM test.test;
INSERT INTO test.test VALUES('2000-01-01', 1, 'test string 1', 1);
INSERT INTO test.test VALUES('2000-01-01', 2, 'test string 2', 2);
@ -50,6 +52,9 @@ SELECT * FROM (SELECT * FROM (SELECT * FROM test.test) ANY LEFT JOIN (SELECT * F
-- Optimize predicate expression with join query and qualified
SELECT * FROM (SELECT 1 AS id, toDate('2000-01-01') AS date FROM system.numbers LIMIT 1) ANY LEFT JOIN (SELECT * FROM test.test) AS b USING date WHERE b.id = 1;
-- Optimize predicate expression with view
SELECT * FROM test.test_view WHERE id = 1;
SELECT '-------Push to having expression, need check.-------';
SELECT id FROM (SELECT min(id) AS id FROM test.test) WHERE id = 1; -- { serverError 277 }
@ -57,3 +62,4 @@ SELECT '-------Compatibility test-------';
SELECT * FROM (SELECT 1 AS id, toDate('2000-01-01') AS date FROM system.numbers LIMIT 1) ANY LEFT JOIN (SELECT * FROM test.test) AS b USING date WHERE b.date = toDate('2000-01-01'); -- {serverError 47}
DROP TABLE IF EXISTS test.test;
DROP TABLE IF EXISTS test.test_view;