我有一个SQLAlchemy模型，例如-
class User(DeclarativeBase):
__tablename__ = 'users'
id = Column(BigInteger, primary_key=True)
email = Column(String(100), unique=True, nullable=False)
name = Column(String(100), nullable=False)
hashed_password = Column(String(100), nullable=False)
is_admin = Column(BOOLEAN, default=False)
is_active = Column(BOOLEAN, default=True)
created = Column(DateTime, default=datetime.now)
modified = Column(DateTime, default=datetime.now, onpudate=datetime.datetime.now)
roles = relationship('Role', secondary=users_roles, back_populates='users', cascade="all, delete-orphan")
permissions = relationship('Permission', secondary=users_permissions, back_populates='users',
cascade="all, delete-orphan")
def __repr__(self):
return "<User(name='%s', email='%s', hashed_password='%s')>" % (self.name, self.email, self.hashed_password)
class Role(DeclarativeBase):
__tablename__ = 'roles'
id = Column(BigInteger, primary_key=True)
name = Column(String(100), unique=True, nullable=False)
users = relationship('User', secondary=users_roles, back_populates='roles',cascade="all, delete-orphan")
permissions = relationship('Permission', secondary=roles_permissions, back_populates='roles',
cascade="all, delete-orphan")
def __repr__(self):
return "<Role(name='%s')>" % self.name
class Permission(DeclarativeBase):
__tablename__ = 'permissions'
id = Column(BigInteger, primary_key=True)
name = Column(String(100), unique=True, nullable=False)
description = Column(String(255))
users = relationship('User', secondary=users_permissions, back_populates='permissions',
cascade="all, delete-orphan")
roles = relationship('Role', secondary=roles_permissions, back_populates='permissions',
cascade="all, delete-orphan")
def __repr__(self):
return "<Permission(name='%s', description='%s')>" % (self.name, self.description)
但是，Alembic无法生成正确的升级，我会尽力做到
def upgrade():
# ### commands auto generated by Alembic - please adjust! ###
# op.drop_table('users')
# ### end Alembic commands ###
op.create_table('roles',
sa.Column('id', sa.BIGINT(), autoincrement=True, nullable=False),
sa.Column('name', sa.String(100), autoincrement=False, nullable=False),
sa.Column('users', BigInteger),
sa.Column('permissions', BigInteger),
sa.PrimaryKeyConstraint('id'),
sa.UniqueConstraint('name', name='roles_name_key')
# sa.ForeignKeyConstraint(['users'], ['users_roles.users_id'], ondelete='CASCADE'),
# sa.ForeignKeyConstraint(['permissions'], ['roles_permissions.permissions_id'], ondelete='CASCADE')
)
op.create_table('permissions',
sa.Column('id', sa.BIGINT(), autoincrement=True, nullable=False),
sa.Column('name', sa.String(100), autoincrement=False, nullable=False),
sa.Column('description', sa.String(255)),
sa.Column('users', BigInteger),
sa.Column('roles', BigInteger),
sa.PrimaryKeyConstraint('id')
# sa.ForeignKeyConstraint(['users'], ['users_permissions.users_id'], ondelete='CASCADE'),
# sa.ForeignKeyConstraint(['roles'], ['role_permissions.roles_id'], ondelete='CASCADE')
)
op.create_table('users_roles',
sa.Column('users_id', BigInteger, sa.ForeignKey('users.id'), primary_key=True),
sa.Column('roles_id', BigInteger, sa.ForeignKey('roles.id'), primary_key=True)
)
op.create_table('users_permissions',
sa.Column('users_id', BigInteger, sa.ForeignKey('users.id'), primary_key=True),
sa.Column('permissions_id', BigInteger, sa.ForeignKey('permissions.id'), primary_key=True)
)
op.create_table('roles_permissions',
sa.Column('roles_id', BigInteger, sa.ForeignKey('roles.id'), primary_key=True),
sa.Column('permissions_id', BigInteger, sa.ForeignKey('permissions.id'), primary_key=True)
)
op.drop_constraint('users_name_key', 'users')
op.add_column('users', sa.Column('is_admin', sa.BOOLEAN, autoincrement=False, nullable=False, default=False))
op.add_column('users', sa.Column('is_active', sa.BOOLEAN, autoincrement=False, nullable=False, default=True))
op.add_column('users', sa.Column('created', sa.DateTime, autoincrement=False, nullable=False,
default=datetime.datetime.now))
op.add_column('users', sa.Column('modified', sa.DateTime, autoincrement=False, nullable=False,
default=datetime.datetime.now))
op.add_column('users', sa.Column('roles', BigInteger))
op.add_column('users', sa.Column('permissions', BigInteger))
op.create_foreign_key(constraint_name="users_roles_fk", source_table="users", referent_table="users_roles",
local_cols=["roles"], remote_cols=["roles_id"], ondelete='CASCADE')
op.create_foreign_key("users_permissions_fk", "users", "users_permissions", ["permissions"], ["permissions_id"],ondelete='CASCADE')
op.create_foreign_key("permissions_users_fk", "permissions", "users_permissions", ["users"], ["users_id"],
ondelete='CASCADE')
op.create_foreign_key("permissions_roles_fk", "permissions", "roles_permissions", ["roles"], ["roles_id"],
ondelete='CASCADE')
op.create_foreign_key("roles_users_fk", "roles", "users_roles", ["users"], ["users_id"],
ondelete='CASCADE')
op.create_foreign_key("roles_permissions_fk", "roles", "roles_permissions", ["permissions"], ["permissions_id"],
ondelete='CASCADE')
我有一个错误，users_roles的主键是复合键，我不知道如何声明它，如何使它 sqlalchemy.exc.ProgrammingError：（psycopg2.ProgrammingError）没有唯一的约束匹配给定表“ users_roles”的键 [SQL：“ ALTER TABLE用户添加约束CONSTRAINT users_roles_fk删除级联中的外部键（角色）引用users_roles（roles_id）”]