diff options
Diffstat (limited to 'src/backend/optimizer/path/allpaths.c')
| -rw-r--r-- | src/backend/optimizer/path/allpaths.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c index 9caca94f64b..4cd1bf65e74 100644 --- a/src/backend/optimizer/path/allpaths.c +++ b/src/backend/optimizer/path/allpaths.c @@ -71,6 +71,10 @@ static void set_plain_rel_size(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte); static void set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte); +static void set_tablesample_rel_size(PlannerInfo *root, RelOptInfo *rel, + RangeTblEntry *rte); +static void set_tablesample_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, + RangeTblEntry *rte); static void set_foreign_size(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte); static void set_foreign_pathlist(PlannerInfo *root, RelOptInfo *rel, @@ -265,6 +269,11 @@ set_rel_size(PlannerInfo *root, RelOptInfo *rel, /* Foreign table */ set_foreign_size(root, rel, rte); } + else if (rte->tablesample != NULL) + { + /* Sampled relation */ + set_tablesample_rel_size(root, rel, rte); + } else { /* Plain relation */ @@ -332,6 +341,11 @@ set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, /* Foreign table */ set_foreign_pathlist(root, rel, rte); } + else if (rte->tablesample != NULL) + { + /* Build sample scan on relation */ + set_tablesample_rel_pathlist(root, rel, rte); + } else { /* Plain relation */ @@ -418,6 +432,41 @@ set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) } /* + * set_tablesample_rel_size + * Set size estimates for a sampled relation. + */ +static void +set_tablesample_rel_size(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) +{ + /* Mark rel with estimated output rows, width, etc */ + set_baserel_size_estimates(root, rel); +} + +/* + * set_tablesample_rel_pathlist + * Build access paths for a sampled relation + * + * There is only one possible path - sampling scan + */ +static void +set_tablesample_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte) +{ + Relids required_outer; + Path *path; + + /* + * 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. + */ + required_outer = rel->lateral_relids; + + /* We only do sample scan if it was requested */ + path = create_samplescan_path(root, rel, required_outer); + rel->pathlist = list_make1(path); +} + +/* * set_foreign_size * Set size estimates for a foreign table RTE */ |