static void set_base_rel_sizes(PlannerInfo *root);
static void set_base_rel_pathlists(PlannerInfo *root);
static void set_rel_size(PlannerInfo *root, RelOptInfo *rel,
- Index rti, RangeTblEntry *rte);
+ Index rti, RangeTblEntry *rte);
static void set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
Index rti, RangeTblEntry *rte);
static void set_plain_rel_size(PlannerInfo *root, RelOptInfo *rel,
- RangeTblEntry *rte);
+ RangeTblEntry *rte);
static void set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
RangeTblEntry *rte);
static void set_foreign_size(PlannerInfo *root, RelOptInfo *rel,
- RangeTblEntry *rte);
+ RangeTblEntry *rte);
static void set_foreign_pathlist(PlannerInfo *root, RelOptInfo *rel,
RangeTblEntry *rte);
static void set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
- Index rti, RangeTblEntry *rte);
+ Index rti, RangeTblEntry *rte);
static void set_append_rel_pathlist(PlannerInfo *root, RelOptInfo *rel,
Index rti, RangeTblEntry *rte);
static void generate_mergeappend_paths(PlannerInfo *root, RelOptInfo *rel,
if (brel == NULL)
continue;
- Assert(brel->relid == rti); /* sanity check on array */
+ Assert(brel->relid == rti); /* sanity check on array */
/* ignore RTEs that are "other rels" */
if (brel->reloptkind != RELOPT_BASEREL)
*/
static void
set_rel_size(PlannerInfo *root, RelOptInfo *rel,
- Index rti, RangeTblEntry *rte)
+ Index rti, RangeTblEntry *rte)
{
if (rel->reloptkind == RELOPT_BASEREL &&
relation_excluded_by_constraints(root, rel, rte))
}
break;
case RTE_SUBQUERY:
+
/*
- * Subqueries don't support parameterized paths, so just go
- * ahead and build their paths immediately.
+ * Subqueries don't support making a choice between
+ * parameterized and unparameterized paths, so just go ahead
+ * and build their paths immediately.
*/
set_subquery_pathlist(root, rel, rti, rte);
break;
set_values_size_estimates(root, rel);
break;
case RTE_CTE:
+
/*
- * CTEs don't support parameterized paths, so just go ahead
- * and build their paths immediately.
+ * CTEs don't support making a choice between parameterized
+ * and unparameterized paths, so just go ahead and build their
+ * paths immediately.
*/
if (rte->self_reference)
set_worktable_pathlist(root, rel, rte);
static void
set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
{
+ Relids required_outer;
+
+ /*
+ * We don't support pushing join clauses into the quals of a seqscan, but
+ * it could still have required parameterization due to LATERAL refs in
+ * its tlist. (That can only happen if the seqscan is on a relation
+ * pulled up out of a UNION ALL appendrel.)
+ */
+ required_outer = rel->lateral_relids;
+
/* Consider sequential scan */
- add_path(rel, create_seqscan_path(root, rel, NULL));
+ add_path(rel, create_seqscan_path(root, rel, required_outer));
/* Consider index scans */
create_index_paths(root, rel);
* CE failed, so finish copying/modifying targetlist and join quals.
*
* Note: the resulting childrel->reltargetlist may contain arbitrary
- * expressions, which normally would not occur in a reltargetlist.
- * That is okay because nothing outside of this routine will look at
- * the child rel's reltargetlist. We do have to cope with the case
- * while constructing attr_widths estimates below, though.
+ * expressions, which otherwise would not occur in a reltargetlist.
+ * Code that might be looking at an appendrel child must cope with
+ * such. Note in particular that "arbitrary expression" can include
+ * "Var belonging to another relation", due to LATERAL references.
*/
childrel->joininfo = (List *)
adjust_appendrel_attrs(root,
/*
* It is possible that constraint exclusion detected a contradiction
- * within a child subquery, even though we didn't prove one above.
- * If so, we can skip this child.
+ * within a child subquery, even though we didn't prove one above. If
+ * so, we can skip this child.
*/
if (IS_DUMMY_REL(childrel))
continue;
/*
* Accumulate per-column estimates too. We need not do anything
- * for PlaceHolderVars in the parent list. If child expression
+ * for PlaceHolderVars in the parent list. If child expression
* isn't a Var, or we didn't record a width estimate for it, we
* have to fall back on a datatype-based estimate.
*
int pndx = parentvar->varattno - rel->min_attr;
int32 child_width = 0;
- if (IsA(childvar, Var))
+ if (IsA(childvar, Var) &&
+ ((Var *) childvar)->varno == childrel->relid)
{
- int cndx = ((Var *) childvar)->varattno - childrel->min_attr;
+ int cndx = ((Var *) childvar)->varattno - childrel->min_attr;
child_width = childrel->attr_widths[cndx];
}
int parentRTindex = rti;
List *live_childrels = NIL;
List *subpaths = NIL;
+ bool subpaths_valid = true;
List *all_child_pathkeys = NIL;
List *all_child_outers = NIL;
ListCell *l;
/*
* Generate access paths for each member relation, and remember the
- * cheapest path for each one. Also, identify all pathkeys (orderings)
+ * cheapest path for each one. Also, identify all pathkeys (orderings)
* and parameterizations (required_outer sets) available for the member
* relations.
*/
continue;
/*
- * Child is live, so add its cheapest access path to the Append path
- * we are constructing for the parent.
+ * Child is live, so add it to the live_childrels list for use below.
*/
- subpaths = accumulate_append_subpath(subpaths,
- childrel->cheapest_total_path);
-
- /* Remember which childrels are live, for logic below */
live_childrels = lappend(live_childrels, childrel);
+ /*
+ * If child has an unparameterized cheapest-total path, add that to
+ * the unparameterized Append path we are constructing for the parent.
+ * If not, there's no workable unparameterized path.
+ */
+ if (childrel->cheapest_total_path->param_info == NULL)
+ subpaths = accumulate_append_subpath(subpaths,
+ childrel->cheapest_total_path);
+ else
+ subpaths_valid = false;
+
/*
* Collect lists of all the available path orderings and
- * parameterizations for all the children. We use these as a
+ * parameterizations for all the children. We use these as a
* heuristic to indicate which sort orderings and parameterizations we
* should build Append and MergeAppend paths for.
*/
/* Have we already seen this param set? */
foreach(lco, all_child_outers)
{
- Relids existing_outers = (Relids) lfirst(lco);
+ Relids existing_outers = (Relids) lfirst(lco);
if (bms_equal(existing_outers, childouter))
{
}
/*
- * Next, build an unordered, unparameterized Append path for the rel.
- * (Note: this is correct even if we have zero or one live subpath due to
- * constraint exclusion.)
+ * If we found unparameterized paths for all children, build an unordered,
+ * unparameterized Append path for the rel. (Note: this is correct even
+ * if we have zero or one live subpath due to constraint exclusion.)
*/
- add_path(rel, (Path *) create_append_path(rel, subpaths, NULL));
+ if (subpaths_valid)
+ add_path(rel, (Path *) create_append_path(rel, subpaths, NULL));
/*
- * Build unparameterized MergeAppend paths based on the collected list of
- * child pathkeys.
+ * Also build unparameterized MergeAppend paths based on the collected
+ * list of child pathkeys.
*/
- generate_mergeappend_paths(root, rel, live_childrels, all_child_pathkeys);
+ if (subpaths_valid)
+ generate_mergeappend_paths(root, rel, live_childrels,
+ all_child_pathkeys);
/*
* Build Append paths for each parameterization seen among the child rels.
* so that not that many cases actually get considered here.)
*
* The Append node itself cannot enforce quals, so all qual checking must
- * be done in the child paths. This means that to have a parameterized
+ * be done in the child paths. This means that to have a parameterized
* Append path, we must have the exact same parameterization for each
* child path; otherwise some children might be failing to check the
* moved-down quals. To make them match up, we can try to increase the
*/
foreach(l, all_child_outers)
{
- Relids required_outer = (Relids) lfirst(l);
- bool ok = true;
+ Relids required_outer = (Relids) lfirst(l);
ListCell *lcr;
/* Select the child paths for an Append with this parameterization */
subpaths = NIL;
+ subpaths_valid = true;
foreach(lcr, live_childrels)
{
RelOptInfo *childrel = (RelOptInfo *) lfirst(lcr);
required_outer, 1.0);
if (cheapest_total == NULL)
{
- ok = false;
+ subpaths_valid = false;
break;
}
}
subpaths = accumulate_append_subpath(subpaths, cheapest_total);
}
- if (ok)
+ if (subpaths_valid)
add_path(rel, (Path *)
create_append_path(rel, subpaths, required_outer));
}
{
cheapest_startup = cheapest_total =
childrel->cheapest_total_path;
- Assert(cheapest_total != NULL);
+ /* Assert we do have an unparameterized path for this child */
+ Assert(cheapest_total->param_info == NULL);
}
/*
* set_subquery_pathlist
* Build the (single) access path for a subquery RTE
*
- * There's no need for a separate set_subquery_size phase, since we don't
- * support parameterized paths for subqueries.
+ * We don't currently support generating parameterized paths for subqueries
+ * by pushing join clauses down into them; it seems too expensive to re-plan
+ * the subquery multiple times to consider different alternatives. So the
+ * subquery will have exactly one path. (The path will be parameterized
+ * if the subquery contains LATERAL references, otherwise not.) Since there's
+ * no freedom of action here, there's no need for a separate set_subquery_size
+ * phase: we just make the path right away.
*/
static void
set_subquery_pathlist(PlannerInfo *root, RelOptInfo *rel,
{
Query *parse = root->parse;
Query *subquery = rte->subquery;
+ Relids required_outer;
bool *differentTypes;
double tuple_fraction;
PlannerInfo *subroot;
*/
subquery = copyObject(subquery);
+ /*
+ * If it's a LATERAL subquery, it might contain some Vars of the current
+ * query level, requiring it to be treated as parameterized, even though
+ * we don't support pushing down join quals into subqueries.
+ */
+ required_outer = rel->lateral_relids;
+
/* We need a workspace for keeping track of set-op type coercions */
differentTypes = (bool *)
palloc0((list_length(subquery->targetList) + 1) * sizeof(bool));
* pseudoconstant clauses; better to have the gating node above the
* subquery.
*
- * Also, if the sub-query has "security_barrier" flag, it means the
+ * Also, if the sub-query has the "security_barrier" flag, it means the
* sub-query originated from a view that must enforce row-level security.
- * We must not push down quals in order to avoid information leaks, either
- * via side-effects or error output.
+ * Then we must not push down quals that contain leaky functions.
*
* Non-pushed-down clauses will get evaluated as qpquals of the
* SubqueryScan node.
else
tuple_fraction = root->tuple_fraction;
+ /* plan_params should not be in use in current query level */
+ Assert(root->plan_params == NIL);
+
/* Generate the plan for the subquery */
rel->subplan = subquery_planner(root->glob, subquery,
root,
&subroot);
rel->subroot = subroot;
+ /* Isolate the params needed by this specific subplan */
+ rel->subplan_params = root->plan_params;
+ root->plan_params = NIL;
+
/*
- * It's possible that constraint exclusion proved the subquery empty.
- * If so, it's convenient to turn it back into a dummy path so that we
- * will recognize appropriate optimizations at this level.
+ * It's possible that constraint exclusion proved the subquery empty. If
+ * so, it's convenient to turn it back into a dummy path so that we will
+ * recognize appropriate optimizations at this level.
*/
if (is_dummy_plan(rel->subplan))
{
pathkeys = convert_subquery_pathkeys(root, rel, subroot->query_pathkeys);
/* Generate appropriate path */
- add_path(rel, create_subqueryscan_path(root, rel, pathkeys, NULL));
+ add_path(rel, create_subqueryscan_path(root, rel, pathkeys, required_outer));
/* Select cheapest path (pretty easy in this case...) */
set_cheapest(rel);
static void
set_function_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
{
+ Relids required_outer;
+
+ /*
+ * We don't support pushing join clauses into the quals of a function
+ * scan, but it could still have required parameterization due to LATERAL
+ * refs in the function expression.
+ */
+ required_outer = rel->lateral_relids;
+
/* Generate appropriate path */
- add_path(rel, create_functionscan_path(root, rel));
+ add_path(rel, create_functionscan_path(root, rel, required_outer));
/* Select cheapest path (pretty easy in this case...) */
set_cheapest(rel);
static void
set_values_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
{
+ Relids required_outer;
+
+ /*
+ * We don't support pushing join clauses into the quals of a values scan,
+ * but it could still have required parameterization due to LATERAL refs
+ * in the values expressions.
+ */
+ required_outer = rel->lateral_relids;
+
/* Generate appropriate path */
- add_path(rel, create_valuesscan_path(root, rel));
+ add_path(rel, create_valuesscan_path(root, rel, required_outer));
/* Select cheapest path (pretty easy in this case...) */
set_cheapest(rel);
* Build the (single) access path for a non-self-reference CTE RTE
*
* There's no need for a separate set_cte_size phase, since we don't
- * support parameterized paths for CTEs.
+ * support join-qual-parameterized paths for CTEs.
*/
static void
set_cte_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
int ndx;
ListCell *lc;
int plan_id;
+ Relids required_outer;
/*
* Find the referenced CTE, and locate the plan previously made for it.
/* Mark rel with estimated output rows, width, etc */
set_cte_size_estimates(root, rel, cteplan);
+ /*
+ * We don't support pushing join clauses into the quals of a CTE scan, but
+ * it could still have required parameterization due to LATERAL refs in
+ * its tlist. (That can only happen if the CTE scan is on a relation
+ * pulled up out of a UNION ALL appendrel.)
+ */
+ required_outer = rel->lateral_relids;
+
/* Generate appropriate path */
- add_path(rel, create_ctescan_path(root, rel));
+ add_path(rel, create_ctescan_path(root, rel, required_outer));
/* Select cheapest path (pretty easy in this case...) */
set_cheapest(rel);
* Build the (single) access path for a self-reference CTE RTE
*
* There's no need for a separate set_worktable_size phase, since we don't
- * support parameterized paths for CTEs.
+ * support join-qual-parameterized paths for CTEs.
*/
static void
set_worktable_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
Plan *cteplan;
PlannerInfo *cteroot;
Index levelsup;
+ Relids required_outer;
/*
* We need to find the non-recursive term's plan, which is in the plan
/* Mark rel with estimated output rows, width, etc */
set_cte_size_estimates(root, rel, cteplan);
+ /*
+ * We don't support pushing join clauses into the quals of a worktable
+ * scan, but it could still have required parameterization due to LATERAL
+ * refs in its tlist. (That can only happen if the worktable scan is on a
+ * relation pulled up out of a UNION ALL appendrel. I'm not sure this is
+ * actually possible given the restrictions on recursive references, but
+ * it's easy enough to support.)
+ */
+ required_outer = rel->lateral_relids;
+
/* Generate appropriate path */
- add_path(rel, create_worktablescan_path(root, rel));
+ add_path(rel, create_worktablescan_path(root, rel, required_outer));
/* Select cheapest path (pretty easy in this case...) */
set_cheapest(rel);
/*
* It would be unsafe to push down window function calls, but at least for
- * the moment we could never see any in a qual anyhow. (The same applies
+ * the moment we could never see any in a qual anyhow. (The same applies
* to aggregates, which we check for in pull_var_clause below.)
*/
Assert(!contain_window_function(qual));
printf("\tpath list:\n");
foreach(l, rel->pathlist)
print_path(root, lfirst(l), 1);
- printf("\n\tcheapest startup path:\n");
- print_path(root, rel->cheapest_startup_path, 1);
- printf("\n\tcheapest total path:\n");
- print_path(root, rel->cheapest_total_path, 1);
+ if (rel->cheapest_startup_path)
+ {
+ printf("\n\tcheapest startup path:\n");
+ print_path(root, rel->cheapest_startup_path, 1);
+ }
+ if (rel->cheapest_total_path)
+ {
+ printf("\n\tcheapest total path:\n");
+ print_path(root, rel->cheapest_total_path, 1);
+ }
printf("\n");
fflush(stdout);
}
projects / postgresql / blobdiff