python连接mysql数据库之MySQLdb/pymysql

Posted 2021-03-10 jkluo

本实验环境

操作系统: win10 

python版本: 3.6.5

mysql版本: 8.0.18

MySQLdb库和pysql库使用方法相同,但是python2和3安装使用MySQLdb的方法如下,python3使用pysql直接pip安装,python2不谈

python2:

pip install MySQL-python

python3:

pip install mysqlclient

具体使用方法如下,如若使用pysql就直接import pysql

import MySQLdb

#连接数据库 connect方法,参数有host,port,user,password,[db],charset

‘‘‘创建数据库‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     charset="utf8")
cursor = db.cursor()  # 新建游标
dbName = "newdb"
sql = "create database %s"%dbName
cursor.execute(sql)
db.close()

‘‘‘创建数据表‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = ‘create table student_info(id int,name varchar(10),address varchar(255),tel int(10))‘
cursor.execute(sql)
db.close()

‘‘‘插入数据‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql1 = "insert into student_info(id,name,address,tel) values(1000002,‘tttttshy‘,‘滨海大道1001‘,1388888888)"
sql2 = "insert into student_info(id,name,address,tel) values(1000005,‘dddddnb‘,‘扬帆大道1010‘,1338888888)"
try:
    cursor.execute(sql1)
    cursor.execute(sql2)
    db.commit()  # 提交操作事务 有内容的修改一定要commit
except:
    print("error")
    db.rollback()# 回滚事务

db.close()

‘‘‘查询数据‘‘‘
# fetchone(): 该方法获取下一个查询结果集。结果集是一个对象
# fetchall():接收全部的返回结果行.
# rowcount: 这是一个只读属性，并返回执行execute()方法后影响的行数。

db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = "select * from student_info"
cursor.execute(sql)
result = cursor.fetchall()
for i in result:
    print(i)
db.close()


‘‘‘修改数据‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = "update student_info set name=‘nnnnnning‘ where name like ‘dddddnb‘"
try:
    cursor.execute(sql)
    db.commit()
except:
    print("error")
    db.rollback()
db.close()


‘‘‘删除数据‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = ‘delete from student_info where name like "nnnnnning"‘
try:
    cursor.execute(sql)
    db.commit()
except:
    print("error")
    db.rollback()
db.close()

‘‘‘删除数据表‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = ‘drop table student_info‘
try:
    cursor.execute(sql)
    db.commit()
except:
    print("error")
    db.rollback()
db.close()

‘‘‘删除数据库‘‘‘
db = MySQLdb.connect(host="localhost",
                     port=3306,
                     user="root",
                     password="123456",
                     db=‘newdb‘,
                     charset="utf8")
cursor = db.cursor()
sql = ‘drop database newdb‘
try:
    cursor.execute(sql)
    db.commit()
except:
    print("error")
    db.rollback()
db.close()