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再python3中连接mysql的模块位pymysql，我们可以通过pip来安装：
1 pip install pymysql
这样我们就可以使用该模块连接mysql了。
连接mysql用到pymysql的Connect()模块，
1 Connect(*args, **kwargs) #Connect方法 2 Establish a connection to the MySQL database. Accepts several 3 arguments: 4 5 host: Host where the database server is located 6 user: Username to log in as 7 password: Password to use. 8 database: Database to use, None to not use a particular one. 9 port: MySQL port to use, default is usually OK. (default: 3306) 10 bind_address: When the client has multiple network interfaces, specify the interface from which to connect to the host. Argument can be a hostname or an IP address. 11 unix_socket: Optionally, you can use a unix socket rather than TCP/IP. 12 charset: Charset you want to use.
连接数据库后需要设置游标（cursor）进行数据库的执行操作conn.cursor():
1 >>> help(conn.cursor) #创建游标 2 Help on method cursor in module pymysql.connections: 3 4 cursor(cursor=None) method of pymysql.connections.Connection instance 5 Create a new cursor to execute queries with
设置了cursor后，就可以写sql语句，使用cursor的实例去执行了,执行用到execute()方法：
1 >>> help(cursor.execute) #execute方法 2 Help on method execute in module pymysql.cursors: 3 4 execute(query, args=None) method of pymysql.cursors.Cursor instance 5 Execute a query 6 7 :param str query: Query to execute. 8 9 :param args: parameters used with query. (optional) 10 :type args: tuple, list or dict 11 12 :return: Number of affected rows 13 :rtype: int 14 15 If args is a list or tuple, %s can be used as a placeholder in the query. 16 If args is a dict, %(name)s can be used as a placeholder in the query.
执行sql语句后，查询返回的结果，可以使用cursor的fetchall()函数查看，这会返回一个元组，每个元组的元素还是一个元组cursor.fetchall()：
1 >>> help(cursor.fetchall) 2 Help on method fetchall in module pymysql.cursors: 3 4 fetchall() method of pymysql.cursors.Cursor instance 5 Fetch all the rows
可以使用for循环逐个查看结果。
下面是一个完整的例子：
1 import pymysql 2 3 conn=pymysql.Connect(host=‘192.168.37.130‘,port=3306,user=‘root‘,password=‘123456‘,database=‘user‘) 4 cursor=conn.cursor(pymysql.cursors.DictCursor) 5 sql=‘select * from users‘ 6 res_num=cursor.execute(sql) 7 print(res_num) 8 res_content=cursor.fetchall() 9 for i in res_content: 10 print(i)
上面模拟了一个简单的数据库查询操作。下面我们在写一个简单的例子：
1 import pymysql 2 3 conn=pymysql.Connect(host=‘192.168.37.130‘,port=3306,user=‘root‘,password=‘123456‘,database=‘user‘) 4 cursor=conn.cursor(pymysql.cursors.DictCursor) 5 name=input(‘Input name:‘).strip() 6 sql=‘select * from users where name like %s‘ 7 res_num=cursor.execute(sql,name ) 8 if res_num>0: 9 res_content=cursor.fetchall() 10 for i in res_content: 11 print(i) 12 else: 13 print(‘Not in database‘)
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原文地址：http://www.cnblogs.com/mingxiazhichan/p/7148192.html
