Re: Is this expected? (Index scanning)

From: "Mitch Vincent" <mitch(at)venux(dot)net>
To: "Stephan Szabo" <sszabo(at)megazone23(dot)bigpanda(dot)com>
Cc: <pgsql-general(at)postgresql(dot)org>
Subject: Re: Is this expected? (Index scanning)
Date: 2001-05-07 03:45:27
Message-ID: 000701c0d6a8$27924100$1251000a@windows
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> In the first and last case the like is anchored at the beginning so it
> uses the name index. The middle case can't use that index, and how
> well distributed are the values of void (is it a boolean?)?

Ahh... I thought that the middle case could use an index, I guess that's why
I was confused..

>It's likely
> that the index isn't very selective, if most of the rows are void='f'
> then that index is probably more expensive to scan than the sequence scan
> would be.

Yep, most of the rows are void='f'..

Thanks!!

-Mitch

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