Flask-SQLALchemy基本使用方法

user = User(name='python')
db.session.add(user)
db.session.commit()

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
 
 
app = Flask(__name__)
 
#设置连接数据库的URL
app.config['SQLALCHEMY_DATABASE_URI'] = 'Mysql://root:mysql@127.0.0.1:3306/Flask_test'
 
#设置每次请求结束后会自动提交数据库中的改动
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
 
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
#查询时会显示原始SQL语句
app.config['SQLALCHEMY_ECHO'] = True
db = SQLAlchemy(app)
 
class Role(db.Model):
    # 定义表名
    __tablename__ = 'roles'
    # 定义列对象
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), unique=True)
    us = db.relationship('User', backref='role')
 
    #repr()方法显示一个可读字符串
    def __repr__(self):
        return 'Role:%s'% self.name
 
class User(db.Model):
    __tablename__ = 'users'
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(64), unique=True, index=True)
    email = db.Column(db.String(64),unique=True)
    pswd = db.Column(db.String(64))
    role_id = db.Column(db.Integer, db.ForeignKey('roles.id'))
 
    def __repr__(self):
        return 'User:%s'%self.name
if __name__ == '__main__':
    db.drop_all()
    db.create_all()
    ro1 = Role(name='admin')
    ro2 = Role(name='user')
    db.session.add_all([ro1,ro2])
    db.session.commit()
    us1 = User(name='wang',email='wang@163.com',pswd='123456',role_id=ro1.id)
    us2 = User(name='zhang',email='zhang@189.com',pswd='201512',role_id=ro2.id)
    us3 = User(name='chen',email='chen@126.com',pswd='987654',role_id=ro2.id)
    us4 = User(name='zhou',email='zhou@163.com',pswd='456789',role_id=ro1.id)
    db.session.add_all([us1,us2,us3,us4])
    db.session.commit()
    app.run(debug=True)

db.create_all()

db.drop_all()

ro1 = Role(name='admin')
db.session.add(ro1)
db.session.commit()
#再次插入一条数据
ro2 = Role(name='user')
db.session.add(ro2)
db.session.commit()

us1 = User(name='wang',email='wang@163.com',pswd='123456',role_id=ro1.id)
us2 = User(name='zhang',email='zhang@189.com',pswd='201512',role_id=ro2.id)
us3 = User(name='chen',email='chen@126.com',pswd='987654',role_id=ro2.id)
us4 = User(name='zhou',email='zhou@163.com',pswd='456789',role_id=ro1.id)
db.session.add_all([us1,us2,us3,us4])
db.session.commit()

User.query.filter_by(name='wang').all()

User.query.first()

User.query.all()

User.query.filter(User.name.endswith('g')).all()

User.query.get()

User.query.filter(User.name!='wang').all()

from sqlalchemy import and_
User.query.filter(and_(User.name!='wang',User.email.endswith('163.com'))).all()

from sqlalchemy import or_
User.query.filter(or_(User.name!='wang',User.email.endswith('163.com'))).all()

from sqlalchemy import not_
User.query.filter(not_(User.name=='chen')).all()

user = User.query.first()
db.session.delete(user)
db.session.commit()
User.query.all()

user = User.query.first()
user.name = 'dong'
db.session.commit()
User.query.first()

User.query.filter_by(name='zhang').update({'name':'li'})

#查询roles表id为1的角色
ro1 = Role.query.get(1)
#查询该角色的所有用户
ro1.us

#查询users表id为3的用户
us1 = User.query.get(3)
#查询用户属于什么角色
us1.role