from sqlalchemy.orm import relationship

from .database import Base


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True)
    email = Column(String, unique=True, index=True)
    hashed_password = Column(String)
    is_active = Column(Boolean, default=True)

    items = relationship("Item", back_populates="owner")


class Item(Base):

from sqlalchemy.orm import relationship

from .database import Base


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True)
    email = Column(String, unique=True, index=True)
    hashed_password = Column(String)
    is_active = Column(Boolean, default=True)

    items = relationship("Item", back_populates="owner")


class Item(Base):

from sqlalchemy.orm import relationship

from .database import Base


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True)
    email = Column(String, unique=True, index=True)
    hashed_password = Column(String)
    is_active = Column(Boolean, default=True)

    items = relationship("Item", back_populates="owner")


class Item(Base):

```Python hl_lines="1  10-13  21-24"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

### Create the relationships

Now create the relationships.

For this, we use `relationship` provided by SQLAlchemy ORM.

This will become, more or less, a "magic" attribute that will contain the values from other tables related to this one.

Also, the best approach was to use already existing standards.

So, before even starting to code **FastAPI**, I spent several months studying the specs for OpenAPI, JSON Schema, OAuth2, etc. Understanding their relationship, overlap, and differences.

## Design

Then I spent some time designing the developer "API" I wanted to have as a user (as a developer using FastAPI).

```Python hl_lines="1  10-13  21-24"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

### ✍ 💛

🔜 ✍ 💛.

👉, 👥 ⚙️ `relationship` 🚚 🇸🇲 🐜.

👉 🔜 ▶️️, 🌅 ⚖️ 🌘, "🎱" 🔢 👈 🔜 🔌 💲 ⚪️➡️ 🎏 🏓 🔗 👉 1️⃣.

```Python hl_lines="2  15  26"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

```Python hl_lines="1  10-13  21-24"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

### 创建关系

现在创建关系。

为此，我们使用SQLAlchemy  ORM提供的`relationship`。

这将或多或少会成为一种“神奇”属性，其中表示该表与其他相关的表中的值。

```Python hl_lines="2  15  26"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

## 0.68.1

* ✨ Add support for `read_with_orm_mode`, to support [SQLModel](https://sqlmodel.tiangolo.com/) relationship attributes. PR [#3757](https://github.com/tiangolo/fastapi/pull/3757) by [@tiangolo](https://github.com/tiangolo).

### Translations

    We are also adding the magic `owner_id` attribute to `Item`.

### Create a `PeeweeGetterDict` for the Pydantic *models* / schemas

When you access a relationship in a Peewee object, like in `some_user.items`, Peewee doesn't provide a `list` of `Item`.

It provides a special custom object of class `ModelSelect`.

            # it now to a dict.
            # Otherwise, there's no way to extract lazy data that requires attribute
            # access instead of dict iteration, e.g. lazy relationships.
            return res
        return _model_dump(
            res,
            by_alias=True,
            exclude_unset=exclude_unset,
            exclude_defaults=exclude_defaults,