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SelectRelatedManager

Author:
realmac
Posted:
September 15, 2011
Language:
Python
Version:
1.2
Score:
0 (after 0 ratings)

Because select_related() only works on ForeignKeys that are not null or blank, when you are customizing the admin, even if you set "list_select_related=True" you can still end up with way too many querys in the Admin changelist. By adding this code to your model you can decrease the queries dramatically.

I found I needed this when I was working with Django apps with a lot of legacy data and I couldn't set the ForeignKey null=False.

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class SelectRelatedManager(models.Manager):
    def get_query_set(self):
        return super(SelectRelatedManager, self)\
            .get_query_set()\
            .select_related('organization')

class SomeModel(models.Model):
    ...
    organization = models.ForeignKey(Organization, blank=True, null=True)
    ....

    objects = SelectRelatedManager()

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