Horton

Transform OR-clauses to SAOP's during index matching

Alexander Korotkov <akorotkov@postgresql.org>

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Commit: d4378c0005e61b1bb78e88097ea6efcdddbe2d6e
Author: Alexander Korotkov <akorotkov@postgresql.org>
Date: 2024-11-23T23:40:20Z
Releases: 18.0 
Transform OR-clauses to SAOP's during index matching

This commit makes match_clause_to_indexcol() match
"(indexkey op C1) OR (indexkey op C2) ... (indexkey op CN)" expression
to the index while transforming it into "indexkey op ANY(ARRAY[C1, C2, ...])"
(ScalarArrayOpExpr node).

This transformation allows handling long OR-clauses with single IndexScan
avoiding diving them into a slower BitmapOr.

We currently restrict Ci to be either Const or Param to apply this
transformation only when it's clearly beneficial.  However, in the future,
we might switch to a liberal understanding of constants, as it is in other
cases.

Discussion: https://postgr.es/m/567ED6CA.2040504%40sigaev.ru
Author: Alena Rybakina, Andrey Lepikhov, Alexander Korotkov
Reviewed-by: Peter Geoghegan, Ranier Vilela, Alexander Korotkov, Robert Haas
Reviewed-by: Jian He, Tom Lane, Nikolay Shaplov

Files

PathChange+/−
src/backend/optimizer/path/indxpath.c modified +280 −4
src/test/regress/expected/create_index.out modified +255 −15
src/test/regress/expected/join.out modified +53 −4
src/test/regress/expected/rowsecurity.out modified +7 −0
src/test/regress/expected/stats_ext.out modified +12 −0
src/test/regress/expected/uuid.out modified +31 −0
src/test/regress/sql/create_index.sql modified +69 −0
src/test/regress/sql/join.sql modified +9 −0
src/test/regress/sql/rowsecurity.sql modified +1 −0
src/test/regress/sql/stats_ext.sql modified +3 −0
src/test/regress/sql/uuid.sql modified +12 −0

Discussion