diff options
| -rw-r--r-- | src/backend/optimizer/path/allpaths.c | 45 | ||||
| -rw-r--r-- | src/backend/optimizer/plan/planmain.c | 30 | ||||
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 5 | ||||
| -rw-r--r-- | src/include/nodes/relation.h | 8 |
4 files changed, 49 insertions, 39 deletions
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c index 5f74d3b36d9..738bb308484 100644 --- a/src/backend/optimizer/path/allpaths.c +++ b/src/backend/optimizer/path/allpaths.c @@ -147,6 +147,7 @@ make_one_rel(PlannerInfo *root, List *joinlist) { RelOptInfo *rel; Index rti; + double total_pages; /* * Construct the all_baserels Relids set. @@ -173,10 +174,45 @@ make_one_rel(PlannerInfo *root, List *joinlist) set_base_rel_consider_startup(root); /* - * Compute size estimates and consider_parallel flags for each base rel, - * then generate access paths. + * Compute size estimates and consider_parallel flags for each base rel. */ set_base_rel_sizes(root); + + /* + * We should now have size estimates for every actual table involved in + * the query, and we also know which if any have been deleted from the + * query by join removal, pruned by partition pruning, or eliminated by + * constraint exclusion. So we can now compute total_table_pages. + * + * Note that appendrels are not double-counted here, even though we don't + * bother to distinguish RelOptInfos for appendrel parents, because the + * parents will have pages = 0. + * + * XXX if a table is self-joined, we will count it once per appearance, + * which perhaps is the wrong thing ... but that's not completely clear, + * and detecting self-joins here is difficult, so ignore it for now. + */ + total_pages = 0; + for (rti = 1; rti < root->simple_rel_array_size; rti++) + { + RelOptInfo *brel = root->simple_rel_array[rti]; + + if (brel == NULL) + continue; + + Assert(brel->relid == rti); /* sanity check on array */ + + if (IS_DUMMY_REL(brel)) + continue; + + if (IS_SIMPLE_REL(brel)) + total_pages += (double) brel->pages; + } + root->total_table_pages = total_pages; + + /* + * Generate access paths for each base rel. + */ set_base_rel_pathlists(root); /* @@ -1271,6 +1307,11 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel, * because some places assume rel->tuples is valid for any baserel. */ rel->tuples = parent_rows; + + /* + * Note that we leave rel->pages as zero; this is important to avoid + * double-counting the appendrel tree in total_table_pages. + */ } else { diff --git a/src/backend/optimizer/plan/planmain.c b/src/backend/optimizer/plan/planmain.c index b05adc70c4a..9b6cc9e10f0 100644 --- a/src/backend/optimizer/plan/planmain.c +++ b/src/backend/optimizer/plan/planmain.c @@ -57,8 +57,6 @@ query_planner(PlannerInfo *root, List *tlist, Query *parse = root->parse; List *joinlist; RelOptInfo *final_rel; - Index rti; - double total_pages; /* * If the query has an empty join tree, then it's something easy like @@ -232,34 +230,6 @@ query_planner(PlannerInfo *root, List *tlist, extract_restriction_or_clauses(root); /* - * We should now have size estimates for every actual table involved in - * the query, and we also know which if any have been deleted from the - * query by join removal; so we can compute total_table_pages. - * - * Note that appendrels are not double-counted here, even though we don't - * bother to distinguish RelOptInfos for appendrel parents, because the - * parents will still have size zero. - * - * XXX if a table is self-joined, we will count it once per appearance, - * which perhaps is the wrong thing ... but that's not completely clear, - * and detecting self-joins here is difficult, so ignore it for now. - */ - total_pages = 0; - for (rti = 1; rti < root->simple_rel_array_size; rti++) - { - RelOptInfo *brel = root->simple_rel_array[rti]; - - if (brel == NULL) - continue; - - Assert(brel->relid == rti); /* sanity check on array */ - - if (IS_SIMPLE_REL(brel)) - total_pages += (double) brel->pages; - } - root->total_table_pages = total_pages; - - /* * Ready to do the primary planning. */ final_rel = make_one_rel(root, joinlist); diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index 46de00460d9..0c88c90de4d 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -138,9 +138,8 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent, /* * Estimate relation size --- unless it's an inheritance parent, in which - * case the size will be computed later in set_append_rel_pathlist, and we - * must leave it zero for now to avoid bollixing the total_table_pages - * calculation. + * case the size we want is not the rel's own size but the size of its + * inheritance tree. That will be computed in set_append_rel_size(). */ if (!inhparent) estimate_rel_size(relation, rel->attr_widths - rel->min_attr, diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 88d37236f7d..6fd24203dd6 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -310,7 +310,8 @@ typedef struct PlannerInfo MemoryContext planner_cxt; /* context holding PlannerInfo */ - double total_table_pages; /* # of pages in all tables of query */ + double total_table_pages; /* # of pages in all non-dummy tables of + * query */ double tuple_fraction; /* tuple_fraction passed to query_planner */ double limit_tuples; /* limit_tuples passed to query_planner */ @@ -687,9 +688,8 @@ typedef struct RelOptInfo bool has_eclass_joins; /* T means joininfo is incomplete */ /* used by partitionwise joins: */ - bool consider_partitionwise_join; /* consider partitionwise - * join paths? (if - * partitioned rel) */ + bool consider_partitionwise_join; /* consider partitionwise join + * paths? (if partitioned rel) */ Relids top_parent_relids; /* Relids of topmost parents (if "other" * rel) */ |