Re: BUG #14079: Issues with query

The WHERE is executed before the SELECT. The value of a is not available to
the WHERE clause as it is assigned at the end of the query.

To actually make your query work it would have to read:
select * from (select 1 as a) as b where a = 1

The from provides the data that the where will operate on, the select then
determines what to be returned.

On Fri, 8 Apr 2016 at 18:41 <hector.bejarano@gmail.com> wrote:

> The following bug has been logged on the website:
>
> Bug reference:      14079
> Logged by:          Hector Bejarano
> Email address:      hector.bejarano@gmail.com
> PostgreSQL version: 9.5.0
> Operating system:   Ubuntu 14
> Description:
>
> This query works:
> select 1 as a
>
> But this one fails:
> select 1 as a where a = 1
>
> And I think they should both work.
>
> Regards,
> Hector.
>
>
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