BYTEA, indexes and "like"
От | Alvar Freude |
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Тема | BYTEA, indexes and "like" |
Дата | |
Msg-id | 2808600000.1029674838@gnarzelwicht.delirium-arts.de обсуждение исходный текст |
Ответы |
Re: BYTEA, indexes and "like"
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Список | pgsql-general |
Hi, it seems, that a BYTEA fiels doesn't support indexes in WHERE-Statement with a "like" condition: test=# EXPLAIN ANALYZE SELECT COUNT(*) FROM bytea_test WHERE bytea_field like '\\000\\000\\001%'; NOTICE: QUERY PLAN: Aggregate (cost=668.72..668.72 rows=1 width=0) (actual time=16.63..16.64 rows=1 loops=1) -> Seq Scan on bytea_test (cost=0.00..668.71 rows=1 width=0) (actual time=6.65..15.69 rows=145 loops=1) Total runtime: 16.77 msec But an equal condition uses indexes: test=# EXPLAIN ANALYZE SELECT COUNT(*) FROM bytea_test WHERE bytea_field = '\\000\\000\\001'; NOTICE: QUERY PLAN: Aggregate (cost=5.93..5.93 rows=1 width=0) (actual time=0.10..0.10 rows=1 loops=1) -> Index Scan using bytea_test_bytea_field_idx on bytea_test (cost=0.00..5.93 rows=1 width=0) (actual time=0.05..0.07 rows=1 loops=1) Total runtime: 0.24 msec With text fields instead of bytea indexes are used also with like, but there are no nullbytes allowed and they are sorted using locales (if not switched of). Are there plans to allow also the "like" conditions on bytea indexes? Thnx and Ciao Alvar -- ** ODEM ist für den poldi Award nominiert! http://www.poldiaward.de/ ** http://www.poldiaward.de/index.php?display=detail&cat=audi&item=24 ** http://odem.org/ ** Mehr Projekte: http://alvar.a-blast.org/
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