python-22 MySQL操作

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MySQL

mysql-connector

MySQL官网提供

#测试
import mysql.connector

#安装
python -m pip install mysql-connector

import mysql.connector
#连接
mydb = mysql.connector.connect(host='localhost',user='root',passwd='root')
print(mydb)
#查看数据库
mycursor = mydb.cursor()
mycursor.execute('SHOW DATABASE')
for x in mycursor:
    print(x)
#创建数据库
mycursor = mydb.cursor()
mycursor.execute('CREATE DATABASE runoob_db')
mydb.commit()
mydb.close()

import mysql.connector
#直接打开指定数据库
mydb = mysql.connector.connect(host='localhost',user='root',passwd='root',database='runoob_db')
mycursor = mydb.cursor()
sql = '建表语句/修改语句/删除表'
mycursor.execute('建表语句/修改语句/删除表')
mycursor.execute(sql)
#习惯性将关键字大写
mycursor.execute('DROP TABLE IP EXISTS sites')

#占位符
sql = '(%s,%s)'
val = ('','')
mycursor.execute(sql,val)

#获取所有记录
mycursor.execute('查询语句')
myresult = mycursor.fetchall()
for x in myresult:
    print(x)
#获取第一条记录
mycursor.execute('查询语句')
myresult = mycursor.fetchone()
print(myresult)

#模糊查询
sql = 'SELECT name FROM sites WHERE name LIKE %s '
val = ('%oo%',)
mycursor.execute(sql,val)

#limit  查询量的设置
sql = 'SELECT name FROM sites limit 2 '
mycursor.execute(sql)
#offset 设置开始位置
sql = ' SELECT name FROM sites LIMIT 3 OFFSET 1 '


mydb.commit()
mydb.close()

PyMySQL

Python3中专用于连接MySQL数据库的库

Python2是mysqldb

#安装
pip3 install PyMySQL

import pymysql
#连接
db = pymysql.connect("localhost",'root','root','testdb')
cursor = db.cursor()
cursor.execute('语句')
#预处理    '\'分行
sql = """   \
            \
      """
cursor.execute(sql)

db.commit()
db.close()
# try except