Re: Substring Problem

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От Sam Mason
Тема Re: Substring Problem
Дата
Msg-id 20080513135627.GA1657@frubble.xen.chris-lamb.co.uk
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Ответ на Substring Problem  (Stefan Schwarzer <stefan.schwarzer@grid.unep.ch>)
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On Tue, May 13, 2008 at 03:26:57PM +0200, Stefan Schwarzer wrote:
> SELECT substring(date from 1 for 7) AS stryearmonth, COUNT(id) AS
> countofnumber FROM (SELECT * from downloads ) AS foo GROUP BY
> stryearmonth ORDER BY stryearmonth ASC

Another way of doing this is by using date_trunc, i.e.:

  SELECT date_trunc('month',date) AS yearmonth...

I think it'll still realise it can use indexes (if they're appropriate)
that way.


  Sam

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