diff options
Diffstat (limited to 'src/backend/optimizer/path/costsize.c')
| -rw-r--r-- | src/backend/optimizer/path/costsize.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c index e7f8cec0fed..50f08521bfe 100644 --- a/src/backend/optimizer/path/costsize.c +++ b/src/backend/optimizer/path/costsize.c @@ -1076,9 +1076,9 @@ cost_functionscan(Path *path, PlannerInfo *root, path->rows = baserel->rows; /* - * Estimate costs of executing the function expression. + * Estimate costs of executing the function expression(s). * - * Currently, nodeFunctionscan.c always executes the function to + * Currently, nodeFunctionscan.c always executes the functions to * completion before returning any rows, and caches the results in a * tuplestore. So the function eval cost is all startup cost, and per-row * costs are minimal. @@ -1088,7 +1088,7 @@ cost_functionscan(Path *path, PlannerInfo *root, * estimates for functions tend to be, there's not a lot of point in that * refinement right now. */ - cost_qual_eval_node(&exprcost, rte->funcexpr, root); + cost_qual_eval_node(&exprcost, (Node *) rte->functions, root); startup_cost += exprcost.startup + exprcost.per_tuple; @@ -3845,14 +3845,26 @@ void set_function_size_estimates(PlannerInfo *root, RelOptInfo *rel) { RangeTblEntry *rte; + ListCell *lc; /* Should only be applied to base relations that are functions */ Assert(rel->relid > 0); rte = planner_rt_fetch(rel->relid, root); Assert(rte->rtekind == RTE_FUNCTION); - /* Estimate number of rows the function itself will return */ - rel->tuples = expression_returns_set_rows(rte->funcexpr); + /* + * Estimate number of rows the functions will return. The rowcount of the + * node is that of the largest function result. + */ + rel->tuples = 0; + foreach(lc, rte->functions) + { + RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc); + double ntup = expression_returns_set_rows(rtfunc->funcexpr); + + if (ntup > rel->tuples) + rel->tuples = ntup; + } /* Now estimate number of output rows, etc */ set_baserel_size_estimates(root, rel); |