Python sqlalchemy中相关表的查询
所以我有两张表和这样的细节Python sqlalchemy中相关表的查询,python,mysql,sqlalchemy,Python,Mysql,Sqlalchemy,所以我有两张表和这样的细节 class Employee(Base): __tablename__ = 'employees' id = Column(Integer, Sequence('employee_id_seq'), primary_key=True) name = Column(String(50), nullable=False) ............ class Detail(Base): __tablename__ = 'detai
class Employee(Base):
__tablename__ = 'employees'
id = Column(Integer, Sequence('employee_id_seq'), primary_key=True)
name = Column(String(50), nullable=False)
............
class Detail(Base):
__tablename__ = 'details'
id = Column(Integer, Sequence('detail_id_seq'), primary_key=True)
start_date = Column(String(50), nullable=False)
email = Column(String(50))
employee_id = Column(Integer, ForeignKey('employee.id'))
employee = relationship("Employee", backref=backref('details', order_by=id))
............
for e, d in session.query(Employee, Detail).filter(Employee.id = Detail.employee_id).all():
print e.name, d.email
print Employee.name
print Employee.details.email
如果您只关心少数列，则可以直接在查询中指定它们：
q = session.query(Employee.name, Detail.email).filter(Employee.id == Detail.employee_id).all()
for e, d in q:
print e, d
# query all employees
q = (session.query(Employee)
# load Details in the same query
.outerjoin(Employee.details)
# let SA know that the relationship "Employee.details" is already loaded in this query so that when we access it, SA will not do another query in the database
.options(contains_eager(Employee.details))
).all()
# navigate the results simply as defined in the relationship configuration
for e in q:
print(e)
for d in e.details:
print(" ->", d)
至于你的
重复SQL