sqlalchemy进阶

# 表结构<br>class Group(Base): # 一对多的表,组中可能包含多个用户
    __tablename__ = ‘group‘
    nid = Column(Integer, primary_key=True, autoincrement=True)
    caption = Column(String(32))
 
class User(Base):
    __tablename__ = ‘user‘
    uid = Column(Integer, primary_key=True, autoincrement=True)
    name = Column(String(32))
    gid = Column(Integer, ForeignKey(‘group.nid‘))

# 创建完表之后，建立连接
Session = sessionmaker(bind=engine)
session = Session()

新增Group表数据
session.add_all([
    Group(caption=‘DBA‘),
    Group(caption=‘SA‘),
    ]
)
session.commit()
session.add(Group(caption=‘QA‘))
新建User表数据
session.add_all([
    User(name=‘Bob‘, gid=1),
    User(name=‘Boss‘, gid=2),
    ]
)
session.commit()

class Host(Base):
    __tablename__ = ‘host‘
    nid = Column(Integer, primary_key=True, autoincrement=True)
    hostname = Column(String(32))
    port = Column(String(32))
    ip = Column(String(32))
 
class HostUser(Base):
    __tablename__ = ‘host_user‘
    nid = Column(Integer, primary_key=True, autoincrement=True)
    username = Column(String(32))
 
# 多对多
class HostToHostUser(Base):
    __tablename__ = ‘host_to_host_user‘
    nid = Column(Integer, primary_key=True, autoincrement=True)
 
    # 两个关联的id，以外键的形式存在
    host_id = Column(Integer, ForeignKey(‘host.nid‘))
    host_user_id = Column(Integer, ForeignKey(‘host_user.nid‘))

# 创建完表之后，建立连接
Session = sessionmaker(bind=engine)
session = Session()
# 新增表数据
session.add_all([
    Host(hostname=‘c1‘,port=‘22‘,ip=‘1.1.1.1‘),
    Host(hostname=‘c2‘,port=‘22‘,ip=‘1.1.1.2‘),
    Host(hostname=‘c3‘,port=‘22‘,ip=‘1.1.1.3‘),
    Host(hostname=‘c4‘,port=‘22‘,ip=‘1.1.1.4‘),
    Host(hostname=‘c5‘,port=‘22‘,ip=‘1.1.1.5‘),
])
session.commit()

session.add_all([
    HostUser(username=‘root‘),
    HostUser(username=‘alex‘),
    HostUser(username=‘eric‘),
    HostUser(username=‘bob‘),
])
session.commit()

session.add_all([
    HostToHostUser(host_id=1,host_user_id=1),
    HostToHostUser(host_id=1,host_user_id=2),
    HostToHostUser(host_id=2,host_user_id=3),
    HostToHostUser(host_id=2,host_user_id=2),
    HostToHostUser(host_id=3,host_user_id=4),
    HostToHostUser(host_id=3,host_user_id=3),
])
session.commit()