diff options
| author | Alvaro Herrera | 2020-04-07 20:22:13 +0000 |
|---|---|---|
| committer | Alvaro Herrera | 2020-04-07 20:22:13 +0000 |
| commit | 357889eb17bb9c9336c4f324ceb1651da616fe57 (patch) | |
| tree | ef30422c7a6ebc2844492bd045ffbfeb30e54516 /src/include/optimizer | |
| parent | 26a944cf29ba67bb49f42656dd2be98fe2485f5f (diff) | |
Support FETCH FIRST WITH TIES
WITH TIES is an option to the FETCH FIRST N ROWS clause (the SQL
standard's spelling of LIMIT), where you additionally get rows that
compare equal to the last of those N rows by the columns in the
mandatory ORDER BY clause.
There was a proposal by Andrew Gierth to implement this functionality in
a more powerful way that would yield more features, but the other patch
had not been finished at this time, so we decided to use this one for
now in the spirit of incremental development.
Author: Surafel Temesgen <surafel3000@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Discussion: https://postgr.es/m/CALAY4q9ky7rD_A4vf=FVQvCGngm3LOes-ky0J6euMrg=_Se+ag@mail.gmail.com
Discussion: https://postgr.es/m/87o8wvz253.fsf@news-spur.riddles.org.uk
Diffstat (limited to 'src/include/optimizer')
| -rw-r--r-- | src/include/optimizer/pathnode.h | 1 | ||||
| -rw-r--r-- | src/include/optimizer/planmain.h | 5 |
2 files changed, 5 insertions, 1 deletions
diff --git a/src/include/optimizer/pathnode.h b/src/include/optimizer/pathnode.h index bcd08af753..715a24ad29 100644 --- a/src/include/optimizer/pathnode.h +++ b/src/include/optimizer/pathnode.h @@ -268,6 +268,7 @@ extern ModifyTablePath *create_modifytable_path(PlannerInfo *root, extern LimitPath *create_limit_path(PlannerInfo *root, RelOptInfo *rel, Path *subpath, Node *limitOffset, Node *limitCount, + LimitOption limitOption, int64 offset_est, int64 count_est); extern void adjust_limit_rows_costs(double *rows, Cost *startup_cost, Cost *total_cost, diff --git a/src/include/optimizer/planmain.h b/src/include/optimizer/planmain.h index 4781201001..f3cefe67b8 100644 --- a/src/include/optimizer/planmain.h +++ b/src/include/optimizer/planmain.h @@ -56,7 +56,10 @@ extern Agg *make_agg(List *tlist, List *qual, int numGroupCols, AttrNumber *grpColIdx, Oid *grpOperators, Oid *grpCollations, List *groupingSets, List *chain, double dNumGroups, Size transitionSpace, Plan *lefttree); -extern Limit *make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount); +extern Limit *make_limit(Plan *lefttree, Node *limitOffset, Node *limitCount, + LimitOption limitOption, int uniqNumCols, + AttrNumber *uniqColIdx, Oid *uniqOperators, + Oid *uniqCollations); /* * prototypes for plan/initsplan.c |