Python操作MySQL之pymsql

pymsql是Python中操作MySQL的模块，其使用方法和MySQLdb几乎相同。

下载安装

pip3 install pymysql

使用操作

1、执行SQL

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import pymysql
  
# 创建连接
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='t1',charset='utf8')
# 创建游标
cursor = conn.cursor()
  
# 执行SQL，并返回收影响行数
effect_row = cursor.execute("update hosts set host = '1.1.1.2'")
  
# 执行SQL，并返回受影响行数
#effect_row = cursor.execute("update hosts set host = '1.1.1.2' where nid > %s", (1,))
  
# 执行SQL，并返回受影响行数
#effect_row = cursor.executemany("insert into hosts(host,color_id)values(%s,%s)", [("1.1.1.11",1),("1.1.1.11",2)])
  
  
# 提交，不然无法保存新建或者修改的数据
conn.commit()
  
# 关闭游标
cursor.close()
# 关闭连接
conn.close()

2、获取新创建数据自增ID

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import pymysql
  
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='t1')
cursor = conn.cursor()
cursor.executemany("insert into hosts(host,color_id)values(%s,%s)", [("1.1.1.11",1),("1.1.1.11",2)])
conn.commit()
cursor.close()
conn.close()
  
# 获取最新自增ID
new_id = cursor.lastrowid

3、获取查询数据

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import pymysql
  
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='t1')
cursor = conn.cursor()
cursor.execute("select * from hosts")
  
# 获取第一行数据
row_1 = cursor.fetchone()
  
# 获取前n行数据
# row_2 = cursor.fetchmany(3)
# 获取所有数据
# row_3 = cursor.fetchall()
  
conn.commit()
cursor.close()
conn.close()

注：在fetch数据时按照顺序进行，可以使用cursor.scroll(num,mode)来移动游标位置，如：

• cursor.scroll(1,mode='relative')  # 相对当前位置移动
• cursor.scroll(2,mode='absolute') # 相对绝对位置移动

4、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 -*-
import pymysql
  
conn = pymysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='t1')
  
# 游标设置为字典类型
cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
r = cursor.execute("call p1()")
  
result = cursor.fetchone()
  
conn.commit()
cursor.close()
conn.close()

 

5、总结

# author:wanstack

import pymysql

# 创建连接
conn = pymysql.connect(host='127.0.0.1',user='root',password='root1234',port=3306,database='test',charset='utf8')
# 创建游标
cursor = conn.cursor()
# cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)

# 增
# effect_row = cursor.execute("insert into class(caption) values('全站二班')")
# print(effect_row)
# effect_row = cursor.executemany("insert into class(caption) values(%s)",(('python1'),('python2'),('python3')))
# print(effect_row)
# 获取最新自增ID
# new_id = cursor.lastrowid
# print(new_id)

# 删
# effect_row = cursor.execute("delete from class where caption='python1'")
# print(effect_row)

# 改
# effect_row = cursor.execute("update class set caption='Linux' where cid=10")
# print(effect_row)
#
# conn.commit()
# =============== 以上操作均需要conn.commit() 提交之后才会生效，查询不需要提交
# 查

effect_row = cursor.execute('select * from student')
# print(effect_row)
# row_1 = cursor.fetchone()
# print(row_1)
# row_many = cursor.fetchmany(3)
# print(row_many)
# row_all = cursor.fetchall()
# print(row_all)

"""
注：在fetch数据时按照顺序进行，可以使用cursor.scroll(num,mode)来移动游标位置，如：

cursor.scroll(1,mode='relative')  # 相对当前位置移动,1表示往下移动一行，-1表示往上移动一行
cursor.scroll(2,mode='absolute') # 相对绝对位置移动
"""
row_many1 = cursor.fetchmany(3)
print(row_many1)
# cursor.scroll(1,mode='relative')
# cursor.scroll(-2,mode='relative')
cursor.scroll(1,mode='absolute')
row_many2 = cursor.fetchmany(3)
print(row_many2)




cursor.close()
conn.close()