Re: Posible planner improvement? - Mailing list pgsql-performance

From Richard Huxton
Subject Re: Posible planner improvement?
Date
Msg-id 4833FDE5.8090603@archonet.com
Whole thread Raw
In response to Posible planner improvement?  (Albert Cervera Areny <albert@sedifa.com>)
Responses Re: Posible planner improvement?  (Albert Cervera Areny <albert@sedifa.com>)
List pgsql-performance
Albert Cervera Areny wrote:
> I've got a query similar to this:
>
> select * from t1, t2 where t1.id > 158507 and t1.id = t2.id;
>
> That took > 84 minutes (the query was a bit longer but this is the part that
> made the difference) after a little change the query took ~1 second:
>
> select * from t1, t2 where t1.id > 158507 and t2.id > 158507 and t1.id =
> t2.id;

Try posting EXPLAIN ANALYSE SELECT ... for both of those queries and
we'll see why it's better at the second one.

--
   Richard Huxton
   Archonet Ltd

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