Re: Ordering Results by a Supplied Order

Rémi Cura <remi.cura@xxxxxxxxx> · Thu, 6 Feb 2014 10:00:08 +0100

Hey,
 I don"t understand the difference between this ORDINALITY option and adding a "row_number() over()" in the SELECT.

Thanks,

Cheers,
Remi-C

2014-02-06 Vik Fearing <vik.fearing@xxxxxxxxxx>:

    On 02/06/2014 04:16 AM, Michael Sacket
      wrote:

      Often times I
          find it necessary to work with table rows in a specific,
          generally user-supplied order.  It could be anything really
          that requires an ordering that can't come from a natural
          column.  Most of the time this involved manipulating a
          position column from the client application.  In any case,
          I've often found that to be cumbersome, but I think I've come
          up with a solution that some of you may find useful.  

    Up until 9.4, that's a good way to do it.

    Starting from 9.4, you can use the WITH ORDINALITY feature.

    http://www.postgresql.org/docs/devel/static/sql-select.html

    -- 
Vik