Re: Suspected bug: outer WHERE reordered before inner WHERE -> input syntax ERROR - Mailing list pgsql-general

John Keith Hohm wrote:

> select * from (
>   select * from (VALUES ('100'), ('JOHN')) as A (n)
>   where trim(trim(n), '0123456789') = ''
> ) as B where n::integer <> -1;

> I'm also interested in responses of the form "why not just do X?".

Why not just add an "OFFSET 0" in the subselect so that the optimizer
does not flatten the query?

 select * from (
   select * from (VALUES ('100'), ('JOHN')) as A (n)
   where trim(trim(n), '0123456789') = ''
 offset 0) as B where n::integer <> -1;


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Alvaro Herrera                                http://www.CommandPrompt.com/
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