Using sa_type causes Mypy type error

[vinodkumars]

First Check

• I added a very descriptive title here.
• I used the GitHub search to find a similar question and didn't find it.
• I searched the SQLModel documentation, with the integrated search.
• I already searched in Google "How to X in SQLModel" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answer.
• I already checked if it is not related to SQLModel but to Pydantic.
• I already checked if it is not related to SQLModel but to SQLAlchemy.

Commit to Help

• I commit to help with one of those options 👆

Example Code

from sqlmodel import SQLModel, Field
from sqlalchemy import DateTime

class BaseModel(SQLModel):
  created_at:Optional[datetime]=Field(sa_type=DateTime(timezone=True))

Description

Creating a column with sa_type causes a type error with Mypy. Here is the error:

No overload variant of "Field" matches argument type "DateTime"

Operating System

macOS

Operating System Details

No response

SQLModel Version

0.0.18

Python Version

3.11.8

Additional Context

No response

[redb0]

I also faced the same problem. Are there any solutions?

I use Python 3.9.19 and sqlmodel 0.0.19

[dolfandringa]

Same basic thing with pyright:

Argument of type "DateTime" cannot be assigned to parameter "sa_type" of type "Type[Any] | PydanticUndefinedType" in function "Field"

[monchin]

It seems that you should use

from typing import Optional

from datetime import datetime
from sqlmodel import Column, DateTime, Field, SQLModel, func


class DateTimeTest(SQLModel):
    __tablename__ = "date_time_test"
    created_at: Optional[datetime] = Field(
        sa_column=Column(DateTime(timezone=True), server_default=func.now())
    )

[monchin]

You can see more details here