Optional ID value for auto-increment causes type errors when retrieving from database

[davecook88]

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Example Code

class MyModel(DBModel, table=True):

    id: Optional[int] = Field( primary_key=True)

Description

Thanks for the great library. I'm just

If I have a model like this:

class MyModel(DBModel, table=True):

    id: Optional[int] = Field( primary_key=True)

Then when saving new records to the database, the ID is automatically assigned, which is great.

However, when I retrieve the model like this I get type errors

model = session.get(MyModel, 1)
id: int = model.id  # ID may be None error

Is there a way to auto-assign my IDs but also have the ID type defined when retrieving saved records?

Operating System

macOS

Operating System Details

No response

SQLModel Version

0.0.6

Python Version

3.10.4

Additional Context

No response

[antont]

I don't think what you say happens - if you get the object like that, the id will be 1 not None

[phi-friday]

add line assert model.id is not None before declare variable id id = model.id

[RobertRosca]

model = session.get(MyModel, 1)
id: int = model.id  # ID may be None error

The issue here isn't that id may be None, it's that model may be None, as session.get will return None if no entry is found - if you're using VSCode you can see this by hovering over model:

You should add a check to deal model being None before trying to access id and that will solve the problem:

model = session.get(MyModel, 1)
if model is None:
    raise sqlalchemy.exc.NoResultFound

model.id  # no more type warning here

Hope that helps!

[YuriiMotov]

And combine this with previous comment to make type checkers completely happy