Re: Using bind variables for multiple values
From: Shakespeare <whatsin_at_xs4all.nl>
Date: Mon, 24 Nov 2008 16:12:56 +0100
Message-ID: <492ac47b$0$188$e4fe514c@news.xs4all.nl>
Date: Mon, 24 Nov 2008 16:12:56 +0100
Message-ID: <492ac47b$0$188$e4fe514c@news.xs4all.nl>
Robert Klemme schreef:
> All,
>
> <snip>
> I wondered: why is it that the join version does a full table scan but > the IN ( subselect ) version does not?
From a logical point of view I would say: because what you ask for is
something different:
- For an IN clause, 1 occurence is enough to decide if there's a match
- For a join, you specifically ask for all matching occurences.
Shakespeare Received on Mon Nov 24 2008 - 09:12:56 CST