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Diffstat (limited to 'src/backend/optimizer/path/costsize.c')
| -rw-r--r-- | src/backend/optimizer/path/costsize.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/src/backend/optimizer/path/costsize.c b/src/backend/optimizer/path/costsize.c index 4d9f3b4bb6b..1b07ea392d9 100644 --- a/src/backend/optimizer/path/costsize.c +++ b/src/backend/optimizer/path/costsize.c @@ -123,6 +123,7 @@ double cpu_index_tuple_cost = DEFAULT_CPU_INDEX_TUPLE_COST; double cpu_operator_cost = DEFAULT_CPU_OPERATOR_COST; double parallel_tuple_cost = DEFAULT_PARALLEL_TUPLE_COST; double parallel_setup_cost = DEFAULT_PARALLEL_SETUP_COST; +double recursive_worktable_factor = DEFAULT_RECURSIVE_WORKTABLE_FACTOR; int effective_cache_size = DEFAULT_EFFECTIVE_CACHE_SIZE; @@ -5665,10 +5666,11 @@ set_cte_size_estimates(PlannerInfo *root, RelOptInfo *rel, double cte_rows) if (rte->self_reference) { /* - * In a self-reference, arbitrarily assume the average worktable size - * is about 10 times the nonrecursive term's size. + * In a self-reference, we assume the average worktable size is a + * multiple of the nonrecursive term's size. The best multiplier will + * vary depending on query "fan-out", so make its value adjustable. */ - rel->tuples = 10 * cte_rows; + rel->tuples = clamp_row_est(recursive_worktable_factor * cte_rows); } else { |