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yum安装

yum install MySQL-python

使用此模块

import MySQLdb #注意大小写！！

#建立和数据库系统的连接

 conn = MySQLdb.connect(host='localhost', user='root',passwd='root')

#获取操作游标

 cursor = conn.cursor()

#选择数据库

 conn.select_db('python')

#执行SQL,创建一个数据库.

 cursor.execute("""select * from test""")

#获取一条记录,每条记录做为一个元组返回

 result = cursor.fetchone();
 print result
 #print 'ID: %s info: %s' % (result[0],result[1])
 print 'ID: %s info: %s' % result

#获取5条记录，注意由于之前执行有了fetchone()，所以游标已经指到第二条记录了，也就是从第二条开始的所有记录

 print "只获取5条记录:"
 results = cursor.fetchmany(5)
 for r in results:
 print r

print “获取所有结果:”
#重置游标位置，0,为偏移量，mode＝absolute | relative,默认为relative,

 cursor.scroll(0,mode='absolute')
 #获取所有结果
 results = cursor.fetchall()
 for r in results:
 print r
 conn.close()

#关闭连接，释放资源

 cursor.close();

http://www.iteye.com/topic/573092

默认的MySQL数据库，其最大连接数max_connections= 100

查看当前系统连接数设置
MariaDB [(none)]> show variables like ‘max_connections’;

max_connections代表的意义是

查看当前连接详细

show processlist;
show full processlist;

查看当前的连接数

show status like “Threads%”;
+—————————+——-+
| Variable_name | Value |
+—————————+——-+
| Threads_cached | 4 |
| Threads_connected | 3 |
| Threads_connected_reserve | 1 |
| Threads_created | 7 |
| Threads_running | 3 |
+—————————+——-+
5 rows in set (0.00 sec)

status也可以查看当前连接的id号，Threads也是连接数

MariaDB [(none)]> status;
————–
mysql Ver 15.1 Distrib 5.5.33a-MariaDB, for Linux (x86_64) using readline 5.1

Connection id: 6213994
Current database:
Current user: root@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ”
Using delimiter: ;
Server: MariaDB
Server version: 5.5.33a-MariaDB-log MariaDB Server, wsrep_23.7.6.rXXXX
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: latin1
Db characterset: latin1
Client characterset: utf8
Conn. characterset: utf8
UNIX socket: /tmp/mysql.sock
Uptime: 236 days 16 hours 13 min 48 sec

Threads: 95 Questions: 160672130 Slow queries: 2410 Opens: 102274 Flush tables: 2 Open tables: 400 Queries per second avg: 7.857
————–