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Make QuerySet .delete() return a success indicator or counter

See original GitHub issue

Hi, I want to check does the delete action is success, the filter().delete() response NoneType. Thanks.

Issue Analytics

State:
Created 5 years ago
Reactions:2
Comments:6 (4 by maintainers)

Top GitHub Comments

2reactions

abondarcommented, Nov 22, 2018

Well, the fact that there is no exception raised is success message by itself.

Regarding returning something useful: Problem is - standard SQL doesn’t provide anything to get meaningful messages from deleting query.

So if we would want to implement such thing we would have to implement custom solution for each of backends (RETURNING for postgres, for sqlite we could try fetching something from changes() and we would have to do SELECT ROW_COUNT() for MySQL) For now I am not sure it’s really needed, and I am quite sure that it’s shouldn’t be default behavior because it adds overhead that is not required for most of users.

If we would add it I think interface should be something like this: Event.filter(...).delete(return_details=True)

1reaction

grigicommented, Nov 22, 2018

It is a good suggestion. Right now it only ever returns None, but returning a success/count would be better. It doesn’t make sense to return the deleted objects, as they now longer exist.

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