Preventing select query on ForeignKey when the primary key is known
to insert a row to a table that has a one-to-one relationship, you would do this in Django:
mypk=2 # Comes from the POST request
model=MyModel(myField="Hello", myForeignModel=ForeignModel.objects.get(pk=mypk))
model.save()
This will cause a SELECT query followed by an INSERT query.
However, the SELECT query isn't re开发者_运维问答ally necessary as it will be the mypk
that is inserted into the foreign key field. Is there a way to get Django to just insert the primary key without doing a SELECT?
Secondly, are there concurrency issues here (in the event that the primary key would change before the user submits the request). If so, how are these dealt with?
From the docs:
Behind the scenes, Django appends
"_id"
to the field name to create its database column name.
Simply set myForeignModel_id
to the FK value.
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