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use-plancontext-more
Jelte Fennema 2020-01-03 10:37:10 +01:00
parent 53020a7439
commit 093be287e2
1 changed files with 11 additions and 15 deletions
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26
src/backend/distributed/planner/distributed_planner.c
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@ -73,8 +73,10 @@ typedef struct DistributedPlanningContext
Query *parse;
/* A copy of the original parsed query that is given to the planner. This
* doesn't contain the changes that are made to parse. This is NULL for non
* distributed plans, since those don't need it. */
* doesn't contain most of the changes that are made to parse. There's one
* that change that is made for non fast path router queries though, which
* is the assigning of RTE identities using AssignRTEIdentities. This is
* NULL for non distributed plans, since those don't need it. */
Query *originalQuery;
/* the cursor options given to the planner */
@ -194,7 +196,9 @@ distributed_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
{
/*
* We need to copy the parse tree because the FastPathPlanner modifies
* it.
* it. In the next branch we do the same for other distributed queries
* too, but for those it needs to be done AFTER calling
* AssignRTEIdentities.
*/
ctx.originalQuery = copyObject(parse);
}
@ -217,10 +221,9 @@ distributed_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
/*
* standard_planner scribbles on it's input, but for deparsing we need the
* unmodified form. Note that we keep RTE_RELATIONs with their identities
* set, which doesn't break our goals, but, prevents us keeping an extra copy
* of the query tree. Note that we copy the query tree once we're sure it's a
* distributed query.
* unmodified form. Note that before copying we call
* AssignRTEIdentities, which is needed because these identities need
* to be present in the copied query too.
*/
rteIdCounter = AssignRTEIdentities(rangeTableList, rteIdCounter);
ctx.originalQuery = copyObject(parse);
@ -250,16 +253,9 @@ distributed_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
PG_TRY();
{
/*
* For trivial queries, we're skipping the standard_planner() in
* order to eliminate its overhead.
*
* Otherwise, call into standard planner. This is required because the Citus
* planner relies on both the restriction information per table and parse tree
* transformations made by postgres' planner.
*/
DistributedPlan *delegatedPlan = NULL;
bool hasExternParam = false;
if (fastPathRouterQuery)
{
result = PlanFastPathDistributedStmt(&ctx, distributionKeyValue);