: Re: [PERFORM] optimizing queries using IN and EXISTS
Nick Hofstede writes:
> I'm surprised at the difference in speed/execution plan between two
> logically equivalent queries, one using IN, the other using EXISTS.
> (At least I think they are logically equivalent)
> SELE
Nick Hofstede writes:
> I'm surprised at the difference in speed/execution plan between two logically
> equivalent queries, one using IN, the other using EXISTS. (At least I think
> they are logically equivalent)
> SELECT *
> FROM foo
> WHERE 'text6' IN (SELECT value
>FRO
Verzonden: woensdag 18 juli 2012 20:40
Aan: Nick Hofstede
CC: pgsql-performance@postgresql.org
Onderwerp: Re: [PERFORM] optimizing queries using IN and EXISTS
On 18 July 2012 17:10, Nick Hofstede wrote:
> Hi,
>
> I'm surprised at the difference in speed/execution plan between two logical
On 18 July 2012 17:10, Nick Hofstede wrote:
> Hi,
>
> I'm surprised at the difference in speed/execution plan between two logically
> equivalent queries, one using IN, the other using EXISTS. (At least I think
> they are logically equivalent)
They are not logically equivalent.
http://www.postg
Hi,
I'm surprised at the difference in speed/execution plan between two logically
equivalent queries, one using IN, the other using EXISTS. (At least I think
they are logically equivalent)
I've created a small setup that illustrates what I mean.
Consider the following tables:
CREATE TABLE foo
