#30374: Paginator UnorderedObjectListWarning on union(all=True) of two sorted
queries
-------------------------------------+-------------------------------------
     Reporter:  Rich Rauenzahn       |                    Owner:  nobody
         Type:  Bug                  |                   Status:  closed
    Component:  Database layer       |                  Version:  master
  (models, ORM)                      |
     Severity:  Normal               |               Resolution:  invalid
     Keywords:                       |             Triage Stage:
                                     |  Unreviewed
    Has patch:  0                    |      Needs documentation:  0
  Needs tests:  0                    |  Patch needs improvement:  0
Easy pickings:  0                    |                    UI/UX:  0
-------------------------------------+-------------------------------------

Comment (by Rich Rauenzahn):

 ...Actually.  I could have sworn I read somewhere that union(all=True)
 preserves order because it doesn't remove duplicates, but I can't find it
 again.

 Postgres says:

 > UNION effectively appends the result of query2 to the result of query1
 (although there is no guarantee that this is the order in which the rows
 are actually returned).
 > Furthermore, it eliminates duplicate rows from its result, in the same
 way as DISTINCT, unless UNION ALL is used.

 In practice it appears to be true, but I don't think it's strictly defined
 in the spec.

-- 
Ticket URL: <https://code.djangoproject.com/ticket/30374#comment:4>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
To view this discussion on the web visit 
https://groups.google.com/d/msgid/django-updates/066.302aefa87e4bf23a012c0bca38f8d726%40djangoproject.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to