django

Commit Graph

Author	SHA1	Message	Date
Anssi Kääriäinen	3fef304ff2	Refactored negated IS NULL handling This one cleaned up add_filter() negated filter generation. As a side effect split_exclude() was cleaned up, too. Refs #19849	2013-02-20 21:34:01 +02:00
Anssi Kääriäinen	01b9c3d519	Fixed #16715 -- Fixed join promotion logic for nested nullable FKs The joins for nested nullable foreign keys were often created as INNER when they should have been OUTER joins. The reason was that only the first join in the chain was promoted correctly. There were also issues with select_related etc. The basic structure for this problem was: A -[nullable]-> B -[nonnull]-> C And the basic problem was that the A->B join was correctly LOUTER, the B->C join not. The major change taken in this patch is that now if we promote a join A->B, we will automatically promote joins B->X for all X in the query. Also, we now make sure there aren't ever join chains like: a LOUTER b INNER c If the a -> b needs to be LOUTER, then the INNER at the end of the chain will cancel the LOUTER join and we have a broken query. Sebastian reported this problem and did also major portions of the patch.	2012-08-25 14:14:45 +03:00

Author

SHA1

Message

Date

Anssi Kääriäinen

3fef304ff2

Refactored negated IS NULL handling

This one cleaned up add_filter() negated filter generation. As a side
effect split_exclude() was cleaned up, too.

Refs #19849

2013-02-20 21:34:01 +02:00

Anssi Kääriäinen

01b9c3d519

Fixed #16715 -- Fixed join promotion logic for nested nullable FKs

The joins for nested nullable foreign keys were often created as INNER
when they should have been OUTER joins. The reason was that only the
first join in the chain was promoted correctly. There were also issues
with select_related etc.

The basic structure for this problem was:
  A -[nullable]-> B -[nonnull]-> C

And the basic problem was that the A->B join was correctly LOUTER,
the B->C join not.

The major change taken in this patch is that now if we promote a join
A->B, we will automatically promote joins B->X for all X in the query.
Also, we now make sure there aren't ever join chains like:
   a LOUTER b INNER c
If the a -> b needs to be LOUTER, then the INNER at the end of the
chain will cancel the LOUTER join and we have a broken query.

Sebastian reported this problem and did also major portions of the
patch.

2012-08-25 14:14:45 +03:00

2 Commits