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0 pointsOJFord2y ago0 comments

If I understand GP correctly, it's 'performing raw SQL queries', or specifically here, 'mapping query fields to model fields': https://docs.djangoproject.com/en/4.2/topics/db/sql/#mapping...

Basically you call `.raw("...")` from some model's queryset, but there's no requirement you actually query that model's table at all.

    class SomeModel:
        name = models.CharField()

    class OtherModel:
        foobar = models.CharField()

    SomeModel.objects.raw("select foobar as name from thisapp_othermodel")

will yield `SomeModel`s with `name`s that are actual `OtherModel` `foobar` values.

0 comments

Izkata2y ago

Yes, but also it's been a long time since I've had any reason to do this, and had gotten "managed = False" mixed up with abstract classes. Abstract classes won't let you do this, but you probably want "managed = False" to prevent migrations from doing stuff in the database, if it's going to be a reporting-only query that doesn't have a backing table.

Also you need to return an "id" column since Django needs a primary key.

On the flipside, you can put that query in the database as a VIEW and point the model at it, also with "managed = False".

OJFordOP2y ago

Oh yes I forgot about that, that can be annoying. But of course, when it's annoying because it doesn't matter, it doesn't matter and you can pass anything back `as id`.

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