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Re: Very inefficient query plan with disjunction in WHERE clause - Mailing list pgsql-performance

From	Віталій Тимчишин
Subject	Re: Very inefficient query plan with disjunction in WHERE clause
Date	June 1, 2009 16:27:16
Msg-id	331e40660906010919v479c690gc41594db8150931a@mail.gmail.com Whole thread Raw
In response to	Very inefficient query plan with disjunction in WHERE clause (Koen Martens <pgsql@metro.cx>)
List	pgsql-performance

2009/6/1 Koen Martens <pgsql@metro.cx>

Now, when I split up the OR in two distinct queries, everything is nice and fast. Both queries run in sub-second time.

Hi.

PostgreSQL simply do not like ORs (can't use indexes in this case), so UNION/UNION ALL is your friend.

Best regards, Vitalii Tymchyshyn

From: Tom Lane
Date: 01 June 2009, 16:19:14
Subject: Re: Using index for bitwise operations?

From: Alan McKay
Date: 01 June 2009, 16:27:30
Subject: Re: Best way to load test a postgresql server