Serialize relationship in SQLModel by default

[JakNowy]

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Example Code

class Search(SQLModel, table=True):
    id: int = Field(default=None, nullable=True, primary_key=True, index=True)
    videos: list["Video"] = Relationship(back_populates="search")


class Video(SQLModel, table=True):
    id: int = Field(default=None, nullable=True, primary_key=True, index=True)
    search_id: int = Field(foreign_key="search.id")
    search: "Search" = Relationship(back_populates="videos")


@router.get("/", response_model=Video)
def read_videos(
    db: Session = Depends(deps.get_db),
):
    return db.query(Video).first()

Description

The code above works fine, but does not return nested dictonary with search relationship. If I simply create

class VideoResponse(SQLModel):
    id: int
    search_id: int
    search: Search

and change response_model to VideoResponse, everything works as I wish. However it brings some redundancy, which in fact SQLModel aims to remove. Would it be possible to make SQLModel serialize the relationship by default?

Operating System

Linux

Operating System Details

No response

SQLModel Version

sqlmodel==0.0.14

Python Version

3.11.4

Additional Context

No response

[wangxin688]

I guess not. explicity is always better than implicity. Also, it's not woring on async session. Use joinload/subquery/selectinload is much more performance way. if you want to load it direclty, may be you should add lazyload to relationship.

[YuriiMotov]

If SQLModel serialized relationships by default, you would have an infinite loop with the models you shared.

I guess it's probably possible to come up with solution how to serialize relationships but prevent infinite loops. If you have such ideas - feel free to share!