sqlalchemy多表查询

from datetime import datetime
from sqlalchemy import Column,Integer,String,Boolean,DateTime,ForeignKey
from sqlalchemy.orm import  relationship
from .connect import Base,session

class User(Base):
    __tablename__='user'
    id=Column(Integer,primary_key=True,autoincrement=True)
    username=Column(String(20),nullable=False)
    passwd=Column(String(50),nullable=False)
    createtime=Column(DateTime,default=datetime.now)
    _locked=Column(Boolean,default=False,nullable=False)
    #在modules中写好查询条件，使用时直接调用
    @classmethod
    def all(cls):
        return session.query(cls).all()
    @classmethod
    def by_name(cls,username):
        return session.query(cls).filter_by(username=username).all()
    @property
    def locked(self):
        return self._locked

    def __repr__(self):
        return '<User(id=%s,username=%s,passwd=%s,createtime=%s,_locked=%s)>'%(
          self.id,
          self.username,
          self.passwd,
          self.createtime,
          self._locked
        )
class UserDetails(Base):
     __tablename__='user_details'
     id=Column(Integer,primary_key=True,autoincrement=True)
     id_card=Column(Integer,nullable=True,unique=True)
     last_login=Column(DateTime)
     login_num=Column(Integer,default=0)
     user_id=Column(Integer,ForeignKey('user.id'))
#bakcref建立反向索引，
     userdetails_for_foreignkey=relationship('User',backref='details',uselist=False,cascade='all')
     def __self__(self):
         return '<UserDetails(id=%s,id_card=%s,last_login=%s,login_num=%s,user_id=%s)>'%(
             self.id,
             self.id_card,
             self.last_login,
             self.login_num,
             self.user_id
         )
if __name__=='__main__':
    Base.metadata.create_all()

user_modules.py