Thread: pgsql: Transform OR-clauses to SAOP's during index matching

pgsql: Transform OR-clauses to SAOP's during index matching

From
Alexander Korotkov
Date:
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

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/d4378c0005e61b1bb78e88097ea6efcdddbe2d6e

Modified Files
--------------
src/backend/optimizer/path/indxpath.c      | 284 ++++++++++++++++++++++++++++-
src/test/regress/expected/create_index.out | 270 +++++++++++++++++++++++++--
src/test/regress/expected/join.out         |  57 +++++-
src/test/regress/expected/rowsecurity.out  |   7 +
src/test/regress/expected/stats_ext.out    |  12 ++
src/test/regress/expected/uuid.out         |  31 ++++
src/test/regress/sql/create_index.sql      |  69 +++++++
src/test/regress/sql/join.sql              |   9 +
src/test/regress/sql/rowsecurity.sql       |   1 +
src/test/regress/sql/stats_ext.sql         |   3 +
src/test/regress/sql/uuid.sql              |  12 ++
11 files changed, 732 insertions(+), 23 deletions(-)