The planner needs to treat GroupingFunc like Aggref for many purposes,
in particular with respect to processing of the argument expressions,
which are not to be evaluated at runtime. A few places hadn't gotten
that memo, notably including subselect.c's processing of outer-level
aggregates. This resulted in assertion failures or wrong plans for
cases in which a GROUPING() construct references an outer aggregation
level.
Also fix missing special cases for GroupingFunc in cost_qual_eval
(resulting in wrong cost estimates for GROUPING(), although it's
not clear that that would affect plan shapes in practice) and in
ruleutils.c (resulting in excess parentheses in pretty-print mode).
Per bug #17088 from Yaoguang Chen. Back-patch to all supported
branches.
Richard Guo, Tom Lane
Discussion: https://postgr.es/m/17088-
e33882b387de7f5c@postgresql.org
/* Avoid recursion for some cases that parser checks not to return a set */
if (IsA(node, Aggref))
return false;
+ if (IsA(node, GroupingFunc))
+ return false;
if (IsA(node, WindowFunc))
return false;
*/
return false; /* don't recurse into children */
}
+ else if (IsA(node, GroupingFunc))
+ {
+ /* Treat this as having cost 1 */
+ context->total.per_tuple += cpu_operator_cost;
+ return false; /* don't recurse into children */
+ }
else if (IsA(node, CoerceViaIO))
{
CoerceViaIO *iocoerce = (CoerceViaIO *) node;
Node *arg = pitem->item;
/*
- * The Var, PlaceHolderVar, or Aggref has already been adjusted to
- * have the correct varlevelsup, phlevelsup, or agglevelsup.
+ * The Var, PlaceHolderVar, Aggref or GroupingFunc has already been
+ * adjusted to have the correct varlevelsup, phlevelsup, or
+ * agglevelsup.
*
- * If it's a PlaceHolderVar or Aggref, its arguments might contain
- * SubLinks, which have not yet been processed (see the comments for
- * SS_replace_correlation_vars). Do that now.
+ * If it's a PlaceHolderVar, Aggref or GroupingFunc, its arguments
+ * might contain SubLinks, which have not yet been processed (see the
+ * comments for SS_replace_correlation_vars). Do that now.
*/
if (IsA(arg, PlaceHolderVar) ||
- IsA(arg, Aggref))
+ IsA(arg, Aggref) ||
+ IsA(arg, GroupingFunc))
arg = SS_process_sublinks(root, arg, false);
splan->parParam = lappend_int(splan->parParam, pitem->paramId);
}
/*
- * Don't recurse into the arguments of an outer PHV or aggregate here. Any
- * SubLinks in the arguments have to be dealt with at the outer query
- * level; they'll be handled when build_subplan collects the PHV or Aggref
- * into the arguments to be passed down to the current subplan.
+ * Don't recurse into the arguments of an outer PHV, Aggref or
+ * GroupingFunc here. Any SubLinks in the arguments have to be dealt with
+ * at the outer query level; they'll be handled when build_subplan
+ * collects the PHV, Aggref or GroupingFunc into the arguments to be
+ * passed down to the current subplan.
*/
if (IsA(node, PlaceHolderVar))
{
if (((Aggref *) node)->agglevelsup > 0)
return node;
}
+ else if (IsA(node, GroupingFunc))
+ {
+ if (((GroupingFunc *) node)->agglevelsup > 0)
+ return node;
+ }
/*
* We should never see a SubPlan expression in the input (since this is
outer_params = NULL;
for (proot = root->parent_root; proot != NULL; proot = proot->parent_root)
{
- /* Include ordinary Var/PHV/Aggref params */
+ /* Include ordinary Var/PHV/Aggref/GroupingFunc params */
foreach(l, proot->plan_params)
{
PlannerParamItem *pitem = (PlannerParamItem *) lfirst(l);
context->varprefix = true;
/*
- * A Param's expansion is typically a Var, Aggref, or upper-level
- * Param, which wouldn't need extra parentheses. Otherwise, insert
- * parens to ensure the expression looks atomic.
+ * A Param's expansion is typically a Var, Aggref, GroupingFunc, or
+ * upper-level Param, which wouldn't need extra parentheses.
+ * Otherwise, insert parens to ensure the expression looks atomic.
*/
need_paren = !(IsA(expr, Var) ||
IsA(expr, Aggref) ||
+ IsA(expr, GroupingFunc) ||
IsA(expr, Param));
if (need_paren)
appendStringInfoChar(context->buf, '(');
case T_NextValueExpr:
case T_NullIfExpr:
case T_Aggref:
+ case T_GroupingFunc:
case T_WindowFunc:
case T_FuncExpr:
/* function-like: name(..) or name[..] */
case T_XmlExpr: /* own parentheses */
case T_NullIfExpr: /* other separators */
case T_Aggref: /* own parentheses */
+ case T_GroupingFunc: /* own parentheses */
case T_WindowFunc: /* own parentheses */
case T_CaseExpr: /* other separators */
return true;
case T_XmlExpr: /* own parentheses */
case T_NullIfExpr: /* other separators */
case T_Aggref: /* own parentheses */
+ case T_GroupingFunc: /* own parentheses */
case T_WindowFunc: /* own parentheses */
case T_CaseExpr: /* other separators */
return true;
| 1 | 2
(4 rows)
+-- test handling of outer GroupingFunc within subqueries
+explain (costs off)
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by cube(v1);
+ QUERY PLAN
+---------------------------
+ MixedAggregate
+ Hash Key: $2
+ Group Key: ()
+ InitPlan 1 (returns $1)
+ -> Result
+ InitPlan 3 (returns $2)
+ -> Result
+ -> Result
+ SubPlan 2
+ -> Result
+(10 rows)
+
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by cube(v1);
+ grouping
+----------
+ 1
+ 0
+(2 rows)
+
+explain (costs off)
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by v1;
+ QUERY PLAN
+---------------------------
+ GroupAggregate
+ Group Key: $2
+ InitPlan 1 (returns $1)
+ -> Result
+ InitPlan 3 (returns $2)
+ -> Result
+ -> Result
+ SubPlan 2
+ -> Result
+(9 rows)
+
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by v1;
+ grouping
+----------
+ 0
+(1 row)
+
-- end
from unnest(array[1,1], array['a','b']) u(i,v)
group by rollup(i, v||'a') order by 1,3;
+-- test handling of outer GroupingFunc within subqueries
+explain (costs off)
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by cube(v1);
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by cube(v1);
+
+explain (costs off)
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by v1;
+select (select grouping(v1)) from (values ((select 1))) v(v1) group by v1;
+
-- end
projects / thirdparty / postgresql.git / commitdiff
