#coding:UTF-8

 from sqlalchemy import Column,String,create_engine

 from sqlalchemy.orm import sessionmaker

 from sqlalchemy.ext.declarative import declarative_base

 import  MySQLdb

 #创建对象的基类：

 Base = declarative_base()

 #定义user对象

 class User(Base):

     __tablename__ =  'user'

     #表的结构

     id = Column(String(20), primary_key=True)

     username = Column(String(20))

 #初始化数据库连接

 #db = SA.create_engine(

 #     "mysql://%s:%s@%s/%s?charset=utf8" % (db_info["user"], db_info["password"], db_info["host"], db_info["db_name"]),

 engine = create_engine("mysql://%s:%s@%s/%s" % ("root","", "localhost", "test" ))

 #engine = create_engine('mysql://root:1111@localhost/test')

 #创建DBsession类型：

 DBSession = sessionmaker(bind=engine)

 #创建session

 session = DBSession()

 #创建Query查询，filter是where查询条件，最后调用one()返回唯一行，如果调用all()就返回所有行

 user = session.query(User).filter(User.id==9).one()

 auser = session.query(User).filter().all()

 #打印类型和对象的name属性

 print 'type==',type(user),",username:",user.username

 for i in  auser:

     print i.id,"username:",i.username

 #关闭session

 session.close()