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From: Alexander Korotkov on 29 Jul 2010 15:38 I think that queries like this: select * from test where val <-> 500 < 1 order by val <-> 500; can also be optimized using knngist. In case of btree_gist this query can be easily rewritten: select * from test where val > 499 and val < 501 order by val <-> 500; But, in pg_trgm it makes it possible to combine different similarity levels in one query. For example: select * from test_trgm order by t <-> 'asdf' < 0.5 or t <-> 'qwer' < 0.4; Is there any chance to handle this syntax also? ---- With best regards, Alexander Korotkov.
From: Robert Haas on 2 Aug 2010 12:14
2010/7/29 Alexander Korotkov <aekorotkov(a)gmail.com>: > But, in pg_trgm it makes it possible to combine different similarity levels > in one query. For example: > select * from test_trgm order by t <-> 'asdf' < 0.5 or t <-> 'qwer' < 0.4; > Is there any chance to handle this syntax also? Maybe I'm missing something, but I don't think that ORDER BY clause makes much sense. OR is going to reduce a true or false value - and it's usually not that interesting to order by a column that can only take one of two values. Am I confused? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise Postgres Company -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers |