安装python的扩展库
pip install Flask-SQLAlchemy
配置信息
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
class Config(object):
DEBUG = True
SQLALCHEMY_DATABASE_URI = "sqlite:///sqlite.db" #数据库创建的位置,在文件的同级目录下
SQLALCHEMY_TRACK_MODIFICATIONS = False
app = Flask(__name__)
app.config.from_object(Config)
db = SQLAlchemy(app)
模型类编写
class 类名(db.Model):
字段名 = db.Column(db.数据类型)
字段名= db.Column(db.Integer # 字符类型,primary_key=True #主键)
字段名= db.Column(db.String(64) #字符串类型,长度为64, nullable=False #不能为空)
创建数据库的命令
db.create_all() #放在代码最后
最新的Flask-SQLAlchemy库可能会创建不了,要再安一个库pymysql,在最前面加上
import pymysql
pymysql.install_as_MySQLdb()
示范
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
import pymysql
pymysql.install_as_MySQLdb()
class Config(object):
DEBUG = True
SQLALCHEMY_DATABASE_URI = "sqlite:///sqlite.db"
SQLALCHEMY_TRACK_MODIFICATIONS = False
app = Flask(__name__)
app.config.from_object(Config)
db = SQLAlchemy(app)
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
user_name = db.Column(db.String(64))
password = db.Column(db.String(64))
db.create_all()
@app.route("/")
def hello():
return "成功!!!"
if __name__ == '__main__':
#这里写增删改查
app.run()
增删改查
增
第一种方法:
user = User(user_name = "xiaohong",password="123")
db.session.add(user)
db.session.commit()
第二种方法:
user = User()
user.user_name = "小黑"
user.password = "123"
db.session.add(user)
db.session.commit()
查
res = User.query.filter_by(user_name="xiaohong").first()
print(res.user_name)
删
res = User.query.filter_by(user_name="xiaohong").first()
db.session.delete(res)
db.session.commit()
改
res = User.query.filter_by(user_name="xiaohong").first()
res.password = "1234"
db.session.commit()
