Re: Query composite index range in an efficient way - Mailing list pgsql-performance

From Havasvölgyi Ottó
Subject Re: Query composite index range in an efficient way
Date
Msg-id 34608c0c0902171055v5f65ce8bv1ca681390f38e719@mail.gmail.com
Whole thread Raw
In response to Re: Query composite index range in an efficient way  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
List pgsql-performance
Thanks, it's a very good idea!
Otto


2009/2/17 Kevin Grittner <Kevin.Grittner@wicourts.gov>
>>> Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:

> WHERE (id1>12 or id1=12 and id2>=34)
>   and (id1<56 or id1=56 and id2<=78)

As others have pointed out, if you are using 8.2 or later, you should
write this as:

WHERE (id1, id2) >= (12, 34) and (id1, id2) <= (56, 78)

On earlier versions you might want to try the logically equivalent:

WHERE (id1 >= 12 and (id1 > 12 or id2 >= 34))
 and (id1 <= 56 and (id1 < 56 or id2 <= 78))

-Kevin

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