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 <[email protected]> Reviewed-by: Álvaro Herrera <[email protected]> Reviewed-by: Tomas Vondra <[email protected]> Discussion: https://postgr.es/m/CALAY4q9ky7rD_A4vf=FVQvCGngm3LOes-ky0J6euMrg=_se...@mail.gmail.com Discussion: https://postgr.es/m/[email protected] Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/357889eb17bb9c9336c4f324ceb1651da616fe57 Modified Files -------------- doc/src/sgml/ref/select.sgml | 15 +-- src/backend/catalog/sql_features.txt | 2 +- src/backend/executor/nodeLimit.c | 160 +++++++++++++++++++++++++++--- src/backend/nodes/copyfuncs.c | 7 ++ src/backend/nodes/equalfuncs.c | 2 + src/backend/nodes/outfuncs.c | 7 ++ src/backend/nodes/readfuncs.c | 6 ++ src/backend/optimizer/plan/createplan.c | 45 ++++++++- src/backend/optimizer/plan/planner.c | 1 + src/backend/optimizer/util/pathnode.c | 2 + src/backend/parser/analyze.c | 21 ++-- src/backend/parser/gram.y | 117 +++++++++++++++++----- src/backend/parser/parse_clause.c | 15 ++- src/backend/utils/adt/ruleutils.c | 27 ++++-- src/include/catalog/catversion.h | 2 +- src/include/nodes/execnodes.h | 5 + src/include/nodes/nodes.h | 13 +++ src/include/nodes/parsenodes.h | 2 + src/include/nodes/pathnodes.h | 1 + src/include/nodes/plannodes.h | 5 + src/include/optimizer/pathnode.h | 1 + src/include/optimizer/planmain.h | 5 +- src/include/parser/parse_clause.h | 3 +- src/test/regress/expected/limit.out | 167 ++++++++++++++++++++++++++++++++ src/test/regress/sql/limit.sql | 48 +++++++++ 25 files changed, 610 insertions(+), 69 deletions(-)
