Dynamically set sql-default value with table-name in SQLModel

[matthiasburger]

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Example Code

class BaseModel(SQLModel):
    @declared_attr
    def __tablename__(cls) -> str:
        return cls.__name__

    guid: Optional[UUID] = Field(default=None, primary_key=True)

class SequencedBaseModel(BaseModel):
    sequence_id: str = Field(sa_column=Column(VARCHAR(50), server_default=text(f"SELECT '{TABLENAME}_' + convert(varchar(10), NEXT VALUE FOR dbo.sequence)")))


class Project(SequencedBaseModel):
    ...

Description

alembic would generate a migration for a table Project with columns guid and sequence_id. The default-value for sequence-id is a sequence which is generated with

SELECT '{TABLENAME}_' + convert(varchar(10), NEXT VALUE FOR dbo.sequence)

and should insert into project-table the values Project_1, Project_2, ...

Any idea on how to set the tablename dynamically? I cannot use a constructor for setting the columns because alembic is ignoring them, I cannot access the __tablename__() function, or cls, because the columns are static...

Operating System

Windows, macOS

Operating System Details

No response

SQLModel Version

0.0.4

Python Version

3.10.10

Additional Context

No response

[matthiasburger]

too bad nobody is answering... found a solution now:

class MyTable(SQLModel):
    sequence_id: str = Field(alias="sequence_id")
  
    @declared_attr
    def sequence_id(cls):
        return Column(
            'sequence_id',
            VARCHAR(50),
            server_default=text(f"SELECT '{cls.__tablename__}_' + convert(varchar(10), NEXT VALUE FOR dbo.sequence)"))