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Re: upgrade 8.1.4 -> latest, sort order subquery

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jef peeraer wrote:
i decide this weekend to upgrade to the latest stable version from an
8.1.4 . Upgrade went smootly, as usual, but today, i've got some
phonecalls of something weird. The query is as follows :


registratie=# select * from module_info where type_module_id = 1;

i combine this with the next query in a subquery

The resulting query , which should return the same result as the first one

Here's where I think you're wrong.

registratie=# select * from module_info where type_module_id in
            (select * from get_parent_type_modules(1));

The order is completely ignored, although there is an order by in the view
'module_info'

You're applying a where clause to the output of your view - filtering it after the sort is done. If that filter is e.g. by a hash then the result will be in a different order (or at least might be).

In general, the only ORDER BY you can rely on is one applied to the final results of your SELECT.

--
  Richard Huxton
  Archonet Ltd


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