• python的pymysql使用方法【转】


    前言

    pymsql是Python中操作MySQL的模块,其使用方法和MySQLdb几乎相同。但目前pymysql支持python3.x而后者不支持3.x版本。

    本文测试python版本:2.6.6。mysql版本:5.7.17

    一、安装

    pip install pymysql

    二、使用操作

    创建测试环境

    mysql> create database zst;
    Query OK, 1 row affected (0.03 sec)
    
    mysql> use zst
    Database changed
    
    mysql> create table tb(id int not null auto_increment, user varchar(64),pass varchar(64),licnese varchar(64),primary key(id));
    Query OK, 0 rows affected (0.08 sec)
    
    mysql> insert into tb(user,pass,licnese)values("u1","u1pass","11113");
    Query OK, 1 row affected (0.11 sec)
    
    mysql> insert into tb(user,pass,licnese)values("u2","u2pass","11113");
    Query OK, 1 row affected (0.05 sec)
    
    mysql> insert into tb(user,pass,licnese)values("u3","u3pass","11113");
    Query OK, 1 row affected (0.00 sec)
    
    mysql> insert into tb(user,pass,licnese)values("u5","u5pass","11113");
    Query OK, 1 row affected (0.00 sec)
    
    mysql> insert into tb(user,pass,licnese)values("u6","u6pass","11113");
    Query OK, 1 row affected (0.01 sec)
    
    mysql> select * from tb;
    +----+------+--------+---------+
    | id | user | pass | licnese |
    +----+------+--------+---------+
    | 1 | u1 | u1pass | 11113 |
    | 2 | u2 | u2pass | 11113 |
    | 3 | u3 | u3pass | 11113 |
    | 4 | u4 | u4pass | 11113 |
    | 5 | u5 | u5pass | 11113 |
    | 6 | u6 | u6pass | 11113 |
    +----+------+--------+---------+
    6 rows in set (0.00 sec)

    1、查询

    #!/usr/bin/python
    #coding: utf-8
    import sys
    import os
    import pymysql
    
    # 创建连接
    conn = pymysql.connect(host='127.0.0.1', port=3307, user='root', passwd='hch123', db='zst', charset='utf8')
    
    # 创建游标
    cursor = conn.cursor()
    
    # 执行SQL
    cursor.execute("select * from tb")
     
    # 获取剩余结果的第一行数据
    row_1 = cursor.fetchone()
    print row_1
    
    # 获取剩余结果前n行数据
    row_2 = cursor.fetchmany(3)
    print row_2
    
    # 获取剩余结果所有数据
    row_3 = cursor.fetchall()
    print row_3
     
    conn.commit()
    cursor.close()
    conn.close()

    执行

    加入try判断

    #!/usr/bin/python
    #coding: utf-8
    import pymysql #导入 pymysql #打开数据库连接 db= pymysql.connect(host="localhost",user="root", password="hch123",db="zst",port=3307) # 使用cursor()方法获取操作游标 cur = db.cursor() #1.查询操作 # 编写sql 查询语句 user 对应我的表名 sql = "select * from user" try: cur.execute(sql) #执行sql语句 results = cur.fetchall() #获取查询的所有记录 print("id","name","password") #遍历结果 for row in results : id = row[0] name = row[1] password = row[2] print(id,name,password) except Exception as e: raise e finally: db.close() #关闭连接

    执行

     2、获取新创建数据自增ID

    可以获取到最新自增的ID,也就是最后插入的一条数据ID

    #!/usr/bin/python
    #coding: utf-8
    
    import sys
    import os
    import pymysql
    
    # 创建连接
    conn = pymysql.connect(host='127.0.0.1', port=3307, user='root', passwd='hch123', db='zst')
    
    # 创建游标
    cursor = conn.cursor()
    
    # 执行SQL
    effect_row = cursor.executemany("insert into tb(user,pass,licnese)values(%s,%s,%s)", [("u3","u3pass","11113"),("u4","u4pass","22224")])
    conn.commit()
    cursor.close()
    conn.close()
    #获取自增id
    new_id = cursor.lastrowid      
    print new_id

    查询结果

    mysql> select * from tb;

    +----+------+--------+---------+ | id | user | pass | licnese | +----+------+--------+---------+ | 1 | u1 | u1pass | 11113 | | 2 | u2 | u2pass | 11113 | | 3 | u3 | u3pass | 11113 | | 4 | u4 | u4pass | 11113 | | 5 | u5 | u5pass | 11113 | | 6 | u6 | u6pass | 11113 | | 7 | u3 | u3pass | 11113 | | 8 | u4 | u4pass | 22224 | +----+------+--------+---------+ 8 rows in set (0.00 sec)

     加入try判断的python脚本

    #!/usr/bin/python
    #coding: utf-8
    
    import pymysql #导入 pymysql
    
    #打开数据库连接
    db= pymysql.connect(host="localhost",user="root",
    password="hch123",db="zst",port=3307)
    
    # 使用cursor()方法获取操作游标
    cur = db.cursor()
    
    sql_insert ="""insert into user(id,username,password) values(5,'liu','1234')"""
    
    try:
    cur.execute(sql_insert)
    #提交
    db.commit()
    except Exception as e:
    #错误回滚
    db.rollback() 
    finally:
    db.close()

    执行

    [root@hchtest3 ~]# python insert_try.py
    
    mysql> select * from zst.user;
    +----+----------+----------+
    | id | username | password |
    +----+----------+----------+
    |  1 | hch      | 11113    |
    |  2 | hch1     | 11114    |
    |  3 | hch2     | 11115    |
    |  4 | liu      | 1234     |
    |  5 | liu      | 1234     |
    +----+----------+----------+
    5 rows in set (0.00 sec)

    3、更新操作

    #!/usr/bin/python
    #coding: utf-8
    
    import pymysql  #导入 pymysql
     
    #打开数据库连接
    db= pymysql.connect(host="localhost",user="root",
         password="hch123",db="zst",port=3307)
     
    # 使用cursor()方法获取操作游标
    cur = db.cursor()
    
    sql_update ="update user set username = '%s' where id = %d"
     
    try:
        cur.execute(sql_update % ("xiongda",3))  #像sql语句传递参数
        #提交
        db.commit()
    except Exception as e:
        #错误回滚
        db.rollback() 
    finally:
        db.close()    

    执行

    mysql> select * from zst.user;
    +----+----------+----------+
    | id | username | password |
    +----+----------+----------+
    |  1 | hch      | 11113    |
    |  2 | hch1     | 11114    |
    |  3 | xiongda  | 11115    |
    |  4 | liu      | 1234     |
    |  5 | liu      | 1234     |
    +----+----------+----------+
    5 rows in set (0.00 sec)

    4、删除操作

    #!/usr/bin/python
    #coding: utf-8
    
    import pymysql  #导入 pymysql
     
    #打开数据库连接
    db= pymysql.connect(host="localhost",user="root",
         password="hch123",db="zst",port=3307)
     
    # 使用cursor()方法获取操作游标
    cur = db.cursor()
    
    sql_delete ="delete from user where id = %d"
     
    try:
        cur.execute(sql_delete % (3))  #像sql语句传递参数
        #提交
        db.commit()
    except Exception as e:
        #错误回滚
        db.rollback() 
    finally:
        db.close()

    执行

    mysql> select * from zst.user;
    +----+----------+----------+
    | id | username | password |
    +----+----------+----------+
    |  1 | hch      | 11113    |
    |  2 | hch1     | 11114    |
    |  4 | liu      | 1234     |
    |  5 | liu      | 1234     |
    +----+----------+----------+
    4 rows in set (0.00 sec)

    5、fetch数据类型

    关于默认获取的数据是元祖类型,如果想要或者字典类型的数据,即:

    #! /usr/bin/env python
    # -*- coding:utf-8 -*-
    # __author__ = "TKQ"
    import pymysql
     
    conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='', db='tkq1')
    #游标设置为字典类型
    cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
    cursor.execute("select * from tb7")
     
    row_1 = cursor.fetchone()
    print row_1  #{u'licnese': 213, u'user': '123', u'nid': 10, u'pass': '213'}
     
    conn.commit()
    cursor.close()
    conn.close()

    转自

    python3.6 使用 pymysql 连接 Mysql 数据库及 简单的增删改查操作 - CSDN博客
    https://blog.csdn.net/qq_37176126/article/details/72824106

    Python中操作mysql的pymysql模块详解 - 明天OoO你好 - 博客园
    http://www.cnblogs.com/wt11/p/6141225.html

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  • 原文地址:https://www.cnblogs.com/paul8339/p/9570015.html
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