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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.databases.postgresql
Subject: Re: Returning a table in SQL
Date: Thu, 28 Aug 2014 21:45:07 +0200
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On 28.08.2014 17:51, Harry Tuttle wrote:
> AP wrote on 27.08.2014 22:37:
>> Actually, I figured it out :
>>
>> with report as (select
>> some_report('Customer','2014-08-01','2014-08-08') cr)
>>   select
>>     (cr).field1,
>>     (cr).field2,
>>     (cr).field3
>>   from report;
>>
>> gives three separated columns.
>>
>> WITH clause is for clarity solely

No, in PostgreSQL it is an optimization fence that actually influences 
optimizer's behavior.  Apart from that I don't see the improvement in 
clarity caused by the additional layer.

> It's still "wrong".
>
> You should really put the function into the from clause.

s/should/must/

> select *
> from some_report('Customer','2014-08-01','2014-08-08')

Kind regards

	robert