diff options
| author | Teodor Sigaev | 2018-01-11 11:49:36 +0000 |
|---|---|---|
| committer | Teodor Sigaev | 2018-01-11 11:49:36 +0000 |
| commit | f50c80dbb17efa39c169f6c510e9464486ff5edc (patch) | |
| tree | 28bd442434d2c59b6f2662e600440a4a30c4374a /contrib/cube/sql | |
| parent | 563a053bdd4b91c5e5560f4bf91220e562326f7d (diff) | |
llow negative coordinate for ~> (cube, int) operator
~> (cube, int) operator was especially designed for knn-gist search.
However, knn-gist supports only ascending ordering of results. Nevertheless
it would be useful to support descending ordering by ~> (cube, int) operator.
We provide workaround for that: negative coordinate give us inversed value
of corresponding cube bound. Therefore, knn search using negative coordinate
gives us an effect of descending ordering by cube bound.
Author: Alexander Korotkov
Reviewed by: Tomas Vondra, Andrey Borodin
Discussion: https://www.postgresql.org/message-id/flat/a9657f6a-b497-36ff-e56-482a2c7e3292@2ndquadrant.com
Diffstat (limited to 'contrib/cube/sql')
| -rw-r--r-- | contrib/cube/sql/cube.sql | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/contrib/cube/sql/cube.sql b/contrib/cube/sql/cube.sql index efa1dbe9e8..f599e7f7c0 100644 --- a/contrib/cube/sql/cube.sql +++ b/contrib/cube/sql/cube.sql @@ -403,6 +403,10 @@ SELECT c~>1, c FROM test_cube ORDER BY c~>1 LIMIT 15; -- ascending by left bound SELECT c~>2, c FROM test_cube ORDER BY c~>2 LIMIT 15; -- ascending by right bound SELECT c~>3, c FROM test_cube ORDER BY c~>3 LIMIT 15; -- ascending by lower bound SELECT c~>4, c FROM test_cube ORDER BY c~>4 LIMIT 15; -- ascending by upper bound +SELECT c~>(-1), c FROM test_cube ORDER BY c~>(-1) LIMIT 15; -- descending by left bound +SELECT c~>(-2), c FROM test_cube ORDER BY c~>(-2) LIMIT 15; -- descending by right bound +SELECT c~>(-3), c FROM test_cube ORDER BY c~>(-3) LIMIT 15; -- descending by lower bound +SELECT c~>(-4), c FROM test_cube ORDER BY c~>(-4) LIMIT 15; -- descending by upper bound -- Same queries with sequential scan (should give the same results as above) RESET enable_seqscan; @@ -414,4 +418,8 @@ SELECT c~>1, c FROM test_cube ORDER BY c~>1 LIMIT 15; -- ascending by left bound SELECT c~>2, c FROM test_cube ORDER BY c~>2 LIMIT 15; -- ascending by right bound SELECT c~>3, c FROM test_cube ORDER BY c~>3 LIMIT 15; -- ascending by lower bound SELECT c~>4, c FROM test_cube ORDER BY c~>4 LIMIT 15; -- ascending by upper bound +SELECT c~>(-1), c FROM test_cube ORDER BY c~>(-1) LIMIT 15; -- descending by left bound +SELECT c~>(-2), c FROM test_cube ORDER BY c~>(-2) LIMIT 15; -- descending by right bound +SELECT c~>(-3), c FROM test_cube ORDER BY c~>(-3) LIMIT 15; -- descending by lower bound +SELECT c~>(-4), c FROM test_cube ORDER BY c~>(-4) LIMIT 15; -- descending by upper bound RESET enable_indexscan; |