python数据库操作（增删改查）

添加数据

import traceback
import pymysql
try:
    connect = pymysql.connect(user="root", password="123456", database="student", charset="utf8")
    cor=connect.cursor()
    sql="insert into stu values(0,\'未闻花名\',99.87);"
    cor.execute(sql)

    connect.commit()
    print("成功添加"+sql+"数据")
except:
    print(traceback.format_exc())

删除数据

import pymysql
import traceback
try:
    connect=pymysql.connect(charset="utf8",user="root",password="123456",database="student")
    cor=connect.cursor()
    sql = "delete from stu where id=207;"
    cor.execute(sql)
    connect.commit()
    print("成功删除数据")
except:
    print(traceback.format_exc())

修改数据

import traceback
import pymysql
try:
    connect=pymysql.connect(user="root",charset="utf8",password="123456",database="student")
    cor=connect.cursor()
    #打2个单引号是不对的！
    sql="update stu set name=\"啊啊啊\",score=45.02 where id=207;"
    cor.execute(sql)
    connect.commit()
    print("数据更改成功")
except:
    print(traceback.format_exc())

查询数据

import traceback
import pymysql
try:
    connect=pymysql.connect(user="root",charset="utf8",password="123456",database="student")
    cor=connect.cursor()
    sql="select * from stu where name like '%杰%';"
    cor.execute(sql)
    all=cor.fetchall()
    for asd in all:
        print(asd)
except:
    print(traceback.format_exc())