MySQL与Python的交互————查询

Posted 2020-11-26 wocaonidaye

Python与MySQL的基本流程

# 导入模块
from pymysql import  *

# 链接数据库
conn = connect(host = "localhost",port = 3306,user=‘root‘,password="135853",database="jing_dong",charset="utf8")

# 获取有标对象
cursor = conn.cursor()

# 通过execute执行sql语句
cursor.execute("select * from goods;")
print(cursor.fetchall())

# 输出表一条数据
print(cursor.fetchone())

# 输出表所有数据
print(cursor.fetchall())

# 输出表指定数据
print(cursor.fetchmany(6))

# 关闭对象
conn.close()
cursor.close()

 

 

mysql与Python的交互

首先先建立一个jing_dong数据库，再来一个goods 和 goods_cates表

开始交互

from  pymysql import *

class Jd:
    def __init__(self):
        # 1.链接数据库
        self.conn = connect(host = "localhost",port = 3306,user=‘root‘,password="135853",database="jing_dong",charset="utf8")
        # 创建油标
        self.curs = self.conn.cursor()

    def __del__(self):
        # 关闭链接
        self.conn.close()
        self.curs.close()

    def execuets(self,sql):
        # 执行MySQL的语句
        self.curs.execute(sql)
        # 遍历接受到的数据
        for i in self.curs.fetchall():
            print(i)

    def cxsy(self):
        """查询所有商品"""
        sql = "select * from goods;"
        self.execuets(sql)


    def spfe(self):
        sql = "select name from goods_cates;"
        self.execuets(sql)

    def ppfl(self):
        sql = "select brand_name from goods group by brand_name;"
        self.execuets(sql)


    def jiemain(self):
        print("-----京东------")
        print("1:所有商品")
        print("2:所有商品分类")
        print("3:所有商品品牌分类")
        return input("请输入对应的功能序号：")

    def run(self):
        while True:
            nus = self.jiemain()
            if nus == "1":
                #查询所有商品
                self.cxsy()
            elif nus == "2":
                #查询所有的商品分类
                self.spfe()
            elif nus == "3":
                #查询所有的商品品牌分类
                self.ppfl()
            else: print("输入错误，请重新输入！！！")

def main():
    jd = Jd()
    jd.run()

if __name__ == ‘__main__‘:
    main()