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,  row affected (0.03 sec)

mysql> use zst
Database changed

mysql> create table tb(id int not null auto_increment, user varchar(),pass varchar(),licnese varchar(),primary key(id));
Query OK,  rows affected (0.08 sec)

mysql> insert into tb(user,pass,licnese)values("u1","u1pass","");
Query OK,  row affected (0.11 sec)

mysql> insert into tb(user,pass,licnese)values("u2","u2pass","");
Query OK,  row affected (0.05 sec)

mysql> insert into tb(user,pass,licnese)values("u3","u3pass","");
Query OK,  row affected (0.00 sec)

mysql> insert into tb(user,pass,licnese)values("u5","u5pass","");
Query OK,  row affected (0.00 sec)

mysql> insert into tb(user,pass,licnese)values("u6","u6pass","");
Query OK,  row affected (0.01 sec)

mysql> select * from tb;
+----+------+--------+---------+
| id | user | pass | licnese |
+----+------+--------+---------+
|  | u1 | u1pass |  |
|  | u2 | u2pass |  |
|  | u3 | u3pass |  |
|  | u4 | u4pass |  |
|  | u5 | u5pass |  |
|  | u6 | u6pass |  |
+----+------+--------+---------+
 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",""),("u4","u4pass","")])
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 |
+----+------+--------+---------+
|   | u1   | u1pass |    |
|   | u2   | u2pass |    |
|   | u3   | u3pass |    |
|   | u4   | u4pass |    |
|   | u5   | u5pass |    |
|   | u6   | u6pass |    |
|   | u3   | u3pass |    |
|   | u4   | u4pass |    |
+----+------+--------+---------+
 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 |
+----+----------+----------+
|   | hch      |     |
|   | hch1     |     |
|   | liu      |      |
|   | liu      |      |
+----+----------+----------+
 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