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Subquery pushdown planner uses original query 

With this commit, we change the input to the logical planner for
subquery pushdown. Before this commit, the planner was relying
on the query tree that is transformed by the postgresql planner.
After this commit, the planner uses the original query. The main
motivation behind this change is the simplify deparsing of
subqueries.
pull/1333/head
Onder Kalaci 2017-03-27 16:43:36 +03:00
parent f5d7ab60ce
commit 96d781e0e9
5 changed files with 22 additions and 12 deletions
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24
src/backend/distributed/planner/multi_logical_planner.c
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@ -104,28 +104,35 @@ static MultiNode * ApplyCartesianProduct(MultiNode *leftNode, MultiNode *rightNo
* Local functions forward declarations for subquery pushdown. Note that these
* functions will be removed with upcoming subqery changes.
*/
static MultiNode * SubqueryPushdownMultiPlanTree(Query *queryTree,
List *subqueryEntryList);
static MultiNode * SubqueryPushdownMultiPlanTree(Query *queryTree);
static void ErrorIfSubqueryJoin(Query *queryTree);
static MultiTable * MultiSubqueryPushdownTable(RangeTblEntry *subqueryRangeTableEntry);
/*
* MultiLogicalPlanCreate takes in a parsed query tree, uses helper functions to
* create logical plan and adds a root node to top of it.
* MultiLogicalPlanCreate takes in both the original query and its corresponding modified
* query tree yield by the standard planner. It uses helper functions to create logical
* plan and adds a root node to top of it. The original query is only used for subquery
* pushdown planning.
*/
MultiTreeRoot *
MultiLogicalPlanCreate(Query *queryTree)
MultiLogicalPlanCreate(Query *originalQuery, Query *queryTree)
{
MultiNode *multiQueryNode = NULL;
MultiTreeRoot *rootNode = NULL;
List *subqueryEntryList = NULL;
List *subqueryEntryList = SubqueryEntryList(queryTree);
/*
* We check the existence of subqueries in the modified query given that
* if postgres already flattened the subqueries, MultiPlanTree() can plan
* corresponding distributed plan.
*/
subqueryEntryList = SubqueryEntryList(queryTree);
if (subqueryEntryList != NIL)
{
if (SubqueryPushdown)
{
multiQueryNode = SubqueryPushdownMultiPlanTree(queryTree, subqueryEntryList);
multiQueryNode = SubqueryPushdownMultiPlanTree(originalQuery);
}
else
{
@ -1982,7 +1989,7 @@ ApplyCartesianProduct(MultiNode *leftNode, MultiNode *rightNode,
* from other parts of code although it causes some code duplication.
*/
static MultiNode *
SubqueryPushdownMultiPlanTree(Query *queryTree, List *subqueryEntryList)
SubqueryPushdownMultiPlanTree(Query *queryTree)
{
List *targetEntryList = queryTree->targetList;
List *qualifierList = NIL;
@ -1997,6 +2004,7 @@ SubqueryPushdownMultiPlanTree(Query *queryTree, List *subqueryEntryList)
MultiExtendedOp *extendedOpNode = NULL;
MultiNode *currentTopNode = NULL;
RangeTblEntry *subqueryRangeTableEntry = NULL;
List *subqueryEntryList = SubqueryEntryList(queryTree);
/* verify we can perform distributed planning on this query */
ErrorIfQueryNotSupported(queryTree);

2
src/backend/distributed/planner/multi_planner.c
View File

@ -311,7 +311,7 @@ CreateDistributedPlan(PlannedStmt *localPlan, Query *originalQuery, Query *query
if ((!distributedPlan || distributedPlan->planningError) && !hasUnresolvedParams)
{
/* Create and optimize logical plan */
MultiTreeRoot *logicalPlan = MultiLogicalPlanCreate(query);
MultiTreeRoot *logicalPlan = MultiLogicalPlanCreate(originalQuery, query);
MultiLogicalPlanOptimize(logicalPlan, plannerRestrictionContext);
/*

2
src/include/distributed/multi_logical_planner.h
View File

@ -180,7 +180,7 @@ extern bool SubqueryPushdown;
/* Function declarations for building logical plans */
extern MultiTreeRoot * MultiLogicalPlanCreate(Query *queryTree);
extern MultiTreeRoot * MultiLogicalPlanCreate(Query *originalQuery, Query *queryTree);
extern bool NeedsDistributedPlanning(Query *queryTree);
extern MultiNode * ParentNode(MultiNode *multiNode);
extern MultiNode * ChildNode(MultiUnaryNode *multiNode);

3
src/test/regress/output/multi_subquery.source
View File

@ -177,7 +177,8 @@ SELECT count(*) FROM
(SELECT l_orderkey FROM lineitem_subquery) UNION ALL
(SELECT 1::bigint)
) b;
ERROR: could not run distributed query with complex table expressions
ERROR: cannot push down this subquery
DETAIL: Union All clauses are currently unsupported
---
-- TEMPORARLY DISABLE UNIONS WITHOUT JOINS
---

3
src/test/regress/output/multi_subquery_0.source
View File

@ -177,7 +177,8 @@ SELECT count(*) FROM
(SELECT l_orderkey FROM lineitem_subquery) UNION ALL
(SELECT 1::bigint)
) b;
ERROR: could not run distributed query with complex table expressions
ERROR: cannot push down this subquery
DETAIL: Union All clauses are currently unsupported
---
-- TEMPORARLY DISABLE UNIONS WITHOUT JOINS
---