python flask框架 数据库的使用

 

#coding:utf8

from flask import Flask  4 from flask_sqlalchemy import SQLAlchemy  5 
app = Flask(__name__)  7 
# 设置链接数据库的url
app.config['SQLALCHEMY_DATABASE_URI']='mysql://root:mysql@127.0.0.1:3306/flask'

# 每次请求结束后自动提交数据
app.config['SQLALCHEMY_COMMIT_ON_TEAMDOWN'] = True 13 
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True 15 
# 查询时会显示原始的sql语句
app.config['SQLALCHEMY_ECHO'] = True 18 
# 注册数据库
db = SQLAlchemy(app) 21 



class Role(db.Model): 26     # 定义表名
    __tablename__ = 'roles'
    # 定义列对象
    id = db.Column(db.Integer,primary_key=True) 30     name = db.Column(db.String(64),unique=True) 31 
    # 关系字段 用于两个方向查
    user = db.relationship('User',backref='rel') 34 
    # repr() 方法现实一个可读字符串
    def __repr__(self): 37         return str(self.name) 38 

class User(db.Model): 41     __tablename__ = 'users'
    id = db.Column(db.Integer,primary_key=True) 43     name = db.Column(db.String(64),unique=True,index=True) 44     email = db.Column(db.String(64),unique=True) 45     pswd = db.Column(db.String(64)) 46     role_id = db.Column(db.Integer,db.ForeignKey("roles.id")) 47 
    def __repr__(self): 49         return str(self.name) 50 

if __name__ == '__main__': 53     db.drop_all()   # 删除表
    db.create_all() # 创建表
    ro1 = Role(name = 'admin')  # 创建对象
    ro2 = Role(name = 'user' ) 57     # 向数据库添加数据
 db.session.add_all([ro1,ro2]) 59     # 提交
    # db.session.commit()


    us1 = User(name='wang', email='[e-mail]', pswd='123456', role_id=ro1.id) 64     us2 = User(name='zhang', email='[e-mail]', pswd='201512', role_id=ro2.id) 65     us3 = User(name='chen', email='[e-mail]', pswd='987654', role_id=ro2.id) 66     us4 = User(name='zhou', email='[e-mail]', pswd='456789', role_id=ro1.id) 67  db.session.add_all([us1, us2, us3, us4]) 68  db.session.commit() 69 

    app.run(debug=True) 72