How to have a AUTO_INCREMENT field different from primary_key

[giovannism20]

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Example Code

class ExampleTable(ExampleTableBase, table=True):
    __tablename__ = "example_table"

    id: UUID | None = Field(default_factory=uuid4, primary_key=True)
    another_auto_increment_field: str | None = Field()

Description

Create a table ExampleTable with id as a primary key and other field called another_auto_increment as not a primary key.

Operating System

Linux

Operating System Details

No response

SQLModel Version

0.0.18

Python Version

3.12

Additional Context

No response

[jonyscathe]

For starters, probably don't make your field a string.
But only way I know of to do this is to use the sa_column_kwargs argument to set autoincrement=True so that will be passed through when SQLModel creates the sqlalchemy Column.
Not a very nice solution, but it works.

another_auto_increment_field: int | None = Field(default=None, sa_column_kwargs={'autoincrement': True})