• 三.实例演示insert/update/delect更新数据库


    1.逻辑图

    2.只是准备

    3.代码展示

     1 import pymysql
     2 conn=pymysql.connect(
     3     host='192.168.199.249',
     4     port=3306,
     5     user='root',
     6     passwd='123456',
     7     db='imooc',
     8     charset='utf8'
     9 )
    10 cursor=conn.cursor()
    11 
    12 sql_insert="insert into user(userid,username) values(10,'name10')"
    13 sql_update="update user set username='name91' where userid=9"
    14 sql_delete="delete from user where userid<3"
    15 
    16 cursor.execute(sql_insert)
    17 print(cursor.rowcount)
    18 cursor.execute(sql_update)
    19 print(cursor.rowcount)
    20 cursor.execute(sql_delete)
    21 print(cursor.rowcount)
    22 
    23 conn.commit()
    24 
    25 cursor.close()
    26 conn.close()

    4.conn.rollback()代码展示

     1 import pymysql
     2 conn=pymysql.connect(
     3     host='192.168.199.249',
     4     port=3306,
     5     user='root',
     6     passwd='123456',
     7     db='imooc',
     8     charset='utf8'
     9 )
    10 cursor=conn.cursor()
    11 
    12 sql_insert="insert into user(userid,username) values(10,'name10')"
    13 sql_update="update user set username='name91' where userid=9"
    14 sql_delete="delete from user where user<3"
    15 
    16 try:
    17     cursor.execute(sql_insert)
    18     print(cursor.rowcount)
    19     cursor.execute(sql_update)
    20     print(cursor.rowcount)
    21     cursor.execute(sql_delete)
    22     print(cursor.rowcount)
    23 
    24     conn.commit()
    25 
    26 except Exception as e:
    27     print(e)
    28     conn.rollback()
    29 
    30 cursor.close()
    31 conn.close()
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  • 原文地址:https://www.cnblogs.com/chenshaoping/p/8563658.html
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