抽屉之Tornado实战（2）--数据库表设计

#一张表对应一个类
class UserInfo(Base):
    #把表名赋给静态字段
    __tablename__ = ‘userinfo‘
    #序号nid，用户名username，密码password，邮箱email，创建时间ctime
    #一行数据就是一个对象
    nid = Column(Integer, primary_key=True, autoincrement=True)
    username = Column(String(32))
    password = Column(String(32))
    email = Column(String(32))
    ctime = Column(TIMESTAMP)
 
    #建立组合索引，这里是方便在登陆采用不同的登陆方式也能更好的索引数据库
    #用户名+密码   和   邮箱+密码   两种组合索引
    __table_args__ = (
        Index(‘ix_user_pwd‘, ‘username‘, ‘password‘),
        Index(‘ix_email_pwd‘, ‘email‘, ‘password‘),
    )

class NewsType(Base):
 
    __tablename__ = ‘newstype‘
 
    nid = Column(Integer, primary_key=True, autoincrement=True)
    caption = Column(String(32))

class News(Base):
 
    __tablename__ = ‘news‘
 
    nid = Column(Integer, primary_key=True, autoincrement=True)
    #建立外键---两个
    user_info_id = Column(Integer, ForeignKey("userinfo.nid"))
    news_type_id = Column(Integer, ForeignKey("newstype.nid"))
    ctime = Column(TIMESTAMP)
    title = Column(String(32))
    url = Column(String(128))
    content = Column(String(150))
 

class Favor(Base):
    #点赞表
    __tablename__ = ‘favor‘
 
    nid = Column(Integer, primary_key=True, autoincrement=True)
    #点赞者id
    user_info_id = Column(Integer, ForeignKey("userinfo.nid"))
    #信息id
    news_id = Column(Integer, ForeignKey("news.nid"))
    ctime = Column(TIMESTAMP)
 
    #建立联合唯一索引
    __table_args__ = (
        UniqueConstraint(‘user_info_id‘, ‘news_id‘, name=‘uix_uid_nid‘),
    )

class Comment(Base):
 
    __tablename__ = ‘comment‘
 
    nid = Column(Integer, primary_key=True, autoincrement=True)
    #评论者id
    user_info_id = Column(Integer, ForeignKey("userinfo.nid"))
    #评论的信息id
    news_id = Column(Integer, ForeignKey("news.nid"))
    #如果为None，就是评论文章，如果是数字就是回复某个人
    reply_id = Column(Integer, ForeignKey("comment.nid"), nullable=True, default=None)
    #顶一下
    up = Column(Integer)
    #踩一下
    down = Column(Integer)
    #创建时间
    ctime = Column(TIMESTAMP)
    #发表设备：手机，电脑，苹果....
    device = Column(String(32))
    #发表内容
    content = Column(String(150))