`sqlalchemy.Column` parameters are not passed forward when set on `sqlmodel.Field` and a column is provided via `sa_column`

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Example Code

name: str = Field(
    sa_column=Column(
        String,
        # ... other attrs not exposed in sqlmodel.Field today
    ),
    index=True  # this is ignored, must be set on `Column` above
)

Description

sqlmodel.Field exposes some but not all fields from sqlalchemy.Column. This means in some cases it is necessary to provide a Column via the sa_column= param on sqlmodel.Field. However, when this is the case the parameters set on sqlmodel.Field are not forwarded to the new sa_column object.

I think the expected behavior here is that parameters set on Field would be combined with those from the sa_column object. Either this or setting a parameter that will be ignored should trigger a warning/exception along the lines of "You have set index but also provided a sqlalchemy.Column object, index will be ignored".

Operating System

Linux

Operating System Details

No response

SQLModel Version

0.0.6

Python Version

3.9.5

Additional Context

No response

[oldfielj-ansto]

@JLHasson I agree that this functionality doesn’t really work as expected. I’ve seen a few other issues where people have run into similar issues, but I’m not sure there is a perfect solution to fix the problem.

Maybe like you suggest a warning should be added, the docs could definitely use some improvement, as I don’t think the “sa_column” parameter is even documented at the moment.

For more complex projects I’d probably suggest people stick with vanilla SQLAlchemy.

[github-actions[bot]]

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