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Rearrange planner to save the whole PlannerInfo (subroot) for a subquery.

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Formerly, set_subquery_pathlist and other creators of plans for subqueries
saved only the rangetable and rowMarks lists from the lower-level
PlannerInfo.  But there's no reason not to remember the whole PlannerInfo,
and indeed this turns out to simplify matters in a number of places.

The immediate reason for doing this was so that the subroot will still be
accessible when we're trying to extract column statistics out of an
already-planned subquery.  But now that I've done it, it seems like a good
code-beautification effort in its own right.

I also chose to get rid of the transient subrtable and subrowmark fields in
SubqueryScan nodes, in favor of having setrefs.c look up the subquery's
RelOptInfo.  That required changing all the APIs in setrefs.c to pass
PlannerInfo not PlannerGlobal, which was a large but quite mechanical
transformation.

One side-effect not foreseen at the beginning is that this finally broke
inheritance_planner's assumption that replanning the same subquery RTE N
times would necessarily give interchangeable results each time.  That
assumption was always pretty risky, but now we really have to make a
separate RTE for each instance so that there's a place to carry the
separate subroots.
This commit is contained in:
Tom Lane
2011-09-03 15:35:12 -04:00
parent 42ad992fdc
commit b3aaf9081a
19 changed files with 394 additions and 304 deletions
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17
src/backend/optimizer/util/clauses.c
View File

@@ -57,7 +57,7 @@ typedef struct
typedef struct
{
ParamListInfo boundParams;
PlannerGlobal *glob;
PlannerInfo *root;
List *active_fns;
Node *case_val;
bool estimate;
@@ -2058,15 +2058,10 @@ eval_const_expressions(PlannerInfo *root, Node *node)
eval_const_expressions_context context;
if (root)
{
context.boundParams = root->glob->boundParams; /* bound Params */
context.glob = root->glob; /* for inlined-function dependencies */
}
else
{
context.boundParams = NULL;
context.glob = NULL;
}
context.root = root; /* for inlined-function dependencies */
context.active_fns = NIL; /* nothing being recursively simplified */
context.case_val = NULL; /* no CASE being examined */
context.estimate = false; /* safe transformations only */
@@ -2097,7 +2092,7 @@ estimate_expression_value(PlannerInfo *root, Node *node)
context.boundParams = root->glob->boundParams; /* bound Params */
/* we do not need to mark the plan as depending on inlined functions */
context.glob = NULL;
context.root = NULL;
context.active_fns = NIL; /* nothing being recursively simplified */
context.case_val = NULL; /* no CASE being examined */
context.estimate = true; /* unsafe transformations OK */
@@ -4123,8 +4118,8 @@ inline_function(Oid funcid, Oid result_type, Oid result_collid,
* Since there is now no trace of the function in the plan tree, we must
* explicitly record the plan's dependency on the function.
*/
if (context->glob)
record_plan_function_dependency(context->glob, funcid);
if (context->root)
record_plan_function_dependency(context->root, funcid);
/*
* Recursively try to simplify the modified expression. Here we must add
@@ -4559,7 +4554,7 @@ inline_set_returning_function(PlannerInfo *root, RangeTblEntry *rte)
* Since there is now no trace of the function in the plan tree, we must
* explicitly record the plan's dependency on the function.
*/
record_plan_function_dependency(root->glob, func_oid);
record_plan_function_dependency(root, func_oid);
return querytree;