Flask SQLAlchemy 设置联合唯一约束/联合外键约束

传统SQLalchemy写法

联合外键约束：

from sqlalchemy import Integer, ForeignKey, ForeignKeyConstraint

mytable = Table(
    "mytable", meta,
    Column("user_id", Integer, ForeignKey("customers.customer_id")),
    Column("post_id", Integer),

    ForeignKeyConstraint(["user_id", "post_id"], ["user.id", "post.id"])
)

联合唯一约束：

from sqlalchemy import Integer, ForeignKey, UniqueConstraint

mytable = Table(
    "mytable", meta,
    Column("user_id", Integer),
    Column("post_id", Integer),

    UniqueConstraint("user_id", "post_id")
)

SQLAlchemy ORM写法：

orm写法这边通过__table_args__传递表级约束

联合外键约束：

from datetime import datetime

from core import db

from sqlalchemy import ForeignKey, ForeignKeyConstraint
from sqlalchemy.dialects.mysql import INTEGER, DATETIME

__all__ = ("UserHistory",)


class UserHistory(db.Model):
    """
    用户浏览历史表

    用于储存用户浏览历史数据
    """
    __table_name__ = "user_info"
    __table_args__ = (ForeignKeyConstraint(["user_id", "post_id"], ["user.id", "post.id"]),)

    # 全局ID 自增
    id = db.Column(INTEGER, index=True, primary_key=True, autoincrement=True, nullable=False)
    # 用户ID 外键
    user_id = db.Column(INTEGER, ForeignKey("user_info.id"))
    # 资讯Id 外键
    post_id = db.Column(INTEGER, ForeignKey("spider_origin_post_data.id"))
    # 浏览时间
    time = db.Column(DATETIME, nullable=False)

联合唯一约束：

from datetime import datetime

from ..core import db

from sqlalchemy import ForeignKey, UniqueConstraint
from sqlalchemy.dialects.mysql import INTEGER, DATETIME

__all__ = ("UserHistory",)


class UserHistory(db.Model):
    """
    用户浏览历史表

    用于储存用户浏览历史数据
    """
    __table_name__ = "user_info"
    __table_args__ = (UniqueConstraint("user_id", "post_id"),)

    # 全局ID 自增
    id = db.Column(INTEGER, index=True, primary_key=True, autoincrement=True, nullable=False)
    # 用户ID 外键
    user_id = db.Column(INTEGER, ForeignKey("user_info.id"))
    # 资讯Id 外键
    post_id = db.Column(INTEGER, ForeignKey("spider_origin_post_data.id"))
    # 浏览时间
    time = db.Column(DATETIME, nullable=False)

声明: 本文采用 BY-NC-SA 协议进行授权，如无注明均为原创，转载请注明转自凤曦的小窝
本文地址: Flask SQLAlchemy 设置联合唯一约束/联合外键约束