Re: Do cast affects index usage?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Anibal David Acosta" <aa(at)devshock(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Do cast affects index usage?
Date: 2012-10-12 20:38:31
Message-ID: 21823.1350074311@sss.pgh.pa.us
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"Anibal David Acosta" <aa(at)devshock(dot)com> writes:
> I have a table with a column of type timestamp with time zone, this column
> has an index

> If I do a select like this
> select * from mytable where cast(my_date as timestamp without time zone) >
> '2012-10-12 20:00:00'
> this query will use the index over the my_date column?

No. The cast seems rather pointless though ...

regards, tom lane

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