Tag: model

How can I set two primary key fields for my models in Django?

django django-models model primary-key python

I have a model like this: How can I have the primary key be the combination of migration and host? Answer Update Django 4.0 Django 4.0 documentation recommends using UniqueConstraint with the constraints option instead of unique_together. Use UniqueConstraint with the constraints option instead. UniqueConstraint provides more functionality than unique_together. unique_together may be deprecated in the future. Original Answer I

How to query database by id using SqlAlchemy?

model python sql sqlalchemy

I need to query a SQLAlchemy database by its id something similar to but for id. How do I do this? [Searching over Google and SO didn’t help] Answer Query has a get function that supports querying by the primary key of the table, which I assume that id is. For example, to query for an object with ID of

Django DateTimeField auto_now_add not working

datetime django model python

In one of the model i have set one timestamp field as follows: While in shell i am able to create a obj and save it, however in my application it is raising a exception that created_datetime field cannot be null. Confused where things went wrong!! How to reslove it. Answer You can do something like this