Re: How to force the parser to use index scan instead of

From: Ron Johnson <ron(dot)l(dot)johnson(at)cox(dot)net>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: How to force the parser to use index scan instead of
Date: 2006-10-08 02:22:53
Message-ID: 452860FD.6020606@cox.net
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On 10/07/06 21:10, Jaime Casanova wrote:
> On 6 Oct 2006 22:32:16 -0700, ck <ck(dot)karthic(at)gmail(dot)com> wrote:
[snip]
>> index scan, Eg
>> select * from h057 where h057001 = 1142::int8
>> the above query uses index scan
>> select * from h057 where h057001 = 1142
>> the above query uses sequential scan.
>
> that's because in 7.3 you must cast to the type of the indexed column
> in order to use the indexes...
>
> had you never seen this?
>
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match

And the default data type for a scalar constant is int4.

- --
Ron Johnson, Jr.
Jefferson LA USA

Is "common sense" really valid?
For example, it is "common sense" to white-power racists that
whites are superior to blacks, and that those with brown skins
are mud people.
However, that "common sense" is obviously wrong.
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