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How can I filter a Django query with a list of values?

I'm sure this is a trivial operation, but I can't figure out how it's done.

There's got to be something smarter than this:

ids = [1, 3, 6, 7, 9]

for id in ids:
    MyModel.objects.filter(pk=id)

I'm looking to get them all in one query with something like:

MyModel.objects.filter(pk=[1, 3, 6, 7, 9])

How can I filter a Django query with a list of values?


p
phoenix

From the Django documentation:

Blog.objects.filter(pk__in=[1, 4, 7])

will it raise error if we pass empty list or return no record ?
@OmkarDeshpande No
@DylanYoung So it will return no record
@OmkarDeshpande Exactly. Though,if you call get(), you will get an ObjectDoesNotExist error of course.
This will return a list, @Omoidashita's answer will return a dictionary of keys to objects.
N
Nilesh

When you have list of items and you want to check the possible values from the list then you can't use =.

The sql query will be like SELECT * FROM mytable WHERE ids=[1, 3, 6, 7, 9] which is not true. You have to use in operator for this so you query will be like SELECT * FROM mytable WHERE ids in (1, 3, 6, 7, 9) for that Django provide __in operator.


+1 for a small explanation. While I know I can read the docs, that doesn't necessarily mean I understood the docs.
F
Francisco

From the Django documentation:

Blog.objects.in_bulk([1])
{1: <Blog: Beatles Blog>}

Blog.objects.in_bulk([1, 2])
{1: <Blog: Beatles Blog>, 2: <Blog: Cheddar Talk>}

Blog.objects.in_bulk([])
{}

Blog.objects.in_bulk()
{1: <Blog: Beatles Blog>, 2: <Blog: Cheddar Talk>, 3: <Blog: Django Weblog>}

Blog.objects.in_bulk(['beatles_blog'], field_name='slug')
{'beatles_blog': <Blog: Beatles Blog>}

This has an advantage over the accepted answer in some cases. It returns a dictionary mapping the queried field to the object.