过程:
1、获取csdn的用户数据库导入本地
试用editplus打开提示内存不足,没找到办法,同事的linux下查看了一下,基本的格式如下:
用户名 # 密码 # 邮箱
用户名 # 密码 # 邮箱
相应数据结构:
CREATE TABLE IF NOT EXISTS `csdn_userdb` (
`id` int(10) NOT NULL auto_increment,
`username` varchar(50) character set gbk NOT NULL,
`password` varchar(50) character set gbk NOT NULL,
`email` varchar(50) character set gbk NOT NULL,
PRIMARY KEY (`id`),
KEY `username` (`username`),
KEY `email` (`email`)
) ENGINE=MyISAM DEFAULT CHARSET=gbk AUTO_INCREMENT=1 ;
一直怀疑fopen打开文件是写入缓存的,但是实践证明速度很快,应该是没有写入缓存,以下为导入数据的代码
$link = mysql_connect('localhost', 'root', 'admin', true);
mysql_select_db('csdn',$link);
$handle = fopen("C:\Users\zhudong\Desktop\www.csdn.net.sql", "r");
while (!feof($handle)){
$i++;
$buffer = fgets($handle);
list($u,$p,$e) = explode(" # ",$buffer);
mysql_query("INSERT INTO csdn_userdb(username,password,email) VALUES ('$u','$p','$e')",$link);
if ($i%1000 == 0) echo $i."\n";
}
fclose($handle);
?>
以上代码效率非常差,故做修改后代码如下:
$link = mysql_connect('localhost', 'root', 'admin', true);
mysql_select_db('csdn',$link);
$handle = fopen("C:\Users\zhudong\Desktop\www.csdn.net.sql", "r");
$perpage = 50;
while (!feof($handle)){
$i++;
$buffer = fgets($handle);
list($u,$p,$e) = explode(" # ",$buffer);
$insertValue[] = "('$u','$p','$e')";
if ($i% $perpage == 0){ $perpage == 0){
$instrtValueString = implode(',',$insertValue);
mysql_query("INSERT INTO csdn_userdb(username,password,email) VALUES $instrtValueString",$link);
echo $i."\n";
$insertValue = array();
}
}
fclose($handle);
为了搞清楚有那些因素对导入数据的效率产生影响,故根据不同的设置进行了测试
CSDN用户总数据 6428600
当$perpage=500;导入后数据:5,902,000;数据丢失526600 丢失率:8%;数据表引擎:MyISAM;索引:有;总耗时 :15分钟
当$perpage=200,导入后数据总数:6,210,200;数据丢失:218400;丢失率:3.3%;数据表引擎: MYISAM ;索引:有;总耗时:30分钟
当$perpage=200,导入后数据总数:6,210,200;数据丢失:218400;丢失率:3.3%;数据表引擎:INNODB;索引:有;总耗时:65分钟
当$perpage=200,导入后数据总数:6,210,200;数据丢失:218400;丢失率:3.3%;数据表引擎:MYISAM;索引:无;总耗时:14分钟(数据导入完毕后单独再建索引)
当$perpage=50,导入后数据总数:6,371,200;数据丢失:57400,丢失率:0.8%;数据表引擎:MYISAM;索引:无:总耗时:20分钟
根据以上情况总结如下:
1、先导入数据后加索引的效率要比先加索引后导入数据的高一倍
2、InnoDB 在单进程数据插入上的效率要比MYISAM低很多
3、当perpage=50的情况下数据丢失率在1%以下
因为通过浏览器执行会有超时的问题,而且效率地下,故通过命令行方式运行,此过程中遇到一点小麻烦耽搁了不少时间
起初我执行如下代码:
php.exe E:\usr\www\importcsdndb.php
但是一直报错:call to undefined function mysql_connect
折腾发现没有载入php.ini
正确代码为:
php.exe -c E:/usr/local/apache2/php.ini importcsdndb.php
2、导入需要匹配的用户数据数据至本地
命令行进入msyql(不会的自己百度)
然后执行:mysql>source C:/Users/zhudong/Desktop/userdb.sql
3、对比筛选用户
对比程序写好了,切记在命令行下运行:
$link = mysql_connect('localhost', 'root', 'admin', true);
mysql_select_db('csdn',$link);
$handle_username = fopen("E:/records_username.txt","a");
//$handle_email = fopen("E:/records_email.txt","a");
$username_num = $email_num = $uid = 0;
while ($uid$nextuid=$uid+10000;
$query = mysql_query("SELECT * FROM pw_members WHERE uid>'$uid' AND uidwhile ($rt = mysql_fetch_array($query,MYSQL_ASSOC)) {
$username = $rt['username'];
$email = $rt['email'];
$query2 = mysql_query("SELECT * FROM scdn_userdb WHERE username='$username' OR email='$email'");
while ($rt2 = mysql_fetch_array($query2,MYSQL_ASSOC)) {
if ($rt['password'] = md5($rt2['password'])) {
if ($rt2['username'] == $username) {
$username_num++;
fwrite($handle_username,'OWN:'.$rt['uid'].'|'.$rt['username'].'|'.$rt['password'].'|'.$rt['email'].' CSDN:'.$rt2['username'].'|'.$rt2['password'].'|'.$rt2['email']."\r\n");
echo 'username_num='.$username_num."\r\n";
continue;
}
/*
if ($rt2['email'] == $email) {
$email_num++;
fwrite($handle_email,'OWN:'.$rt['uid'].'|'.$rt['username'].'|'.$rt['password'].'|'.$rt['email'].' CSDN:'.$rt2['username'].'|'.$rt2['password'].'|'.$rt2['email']."\r\n");
echo 'email_num='.$email_num."\r\n";
}
*/
}
}
mysql_free_result($query2);
}
$uid = $nextuid;
}
?>
您看到的以上的代码是非常蹩脚的,因为其效率特别低 ,几百万的数据,要跑10多个小时,怎么能忘记连表查询这么基本的东西呢,以下为修正后的方法
$link = mysql_connect('localhost', 'root', 'admin', true);
mysql_select_db('csdn',$link);
$handle_username = fopen("E:/records_username.txt","a");
while($uid$nextuid= $uid+10000;
$query = mysql_query("SELECT m.uid,m.username,m.password,m.email,u.password as csdn_password,u.email as csdn_email FROM own_members m LEFT JOIN csdn_userdb u USING(username) WHERE m.uid>'$uid' AND m.uidwhile ($rt = mysql_fetch_array($query,MYSQL_ASSOC)) {
if ($rt['password'] == md5($rt['csdn_password'])) {
$username_num++;
fwrite($handle_username,'OWN:'.$rt['uid'].'|'.$rt['username'].'|'.$rt['password'].'|'.$rt['email'].' CSDN:'.$rt['username'].'|'.$rt['csdn_password'].'|'.$rt['csdn_email']."\r\n");
echo 'username_num='.$username_num."\r\n";
}
}
$uid = $nextuid;
echo 'uid='.$uid;
}
?>
总对比时间25分钟,相比较之前10多个小时的执行真是大有提升
总重名用户:34175
占总会员比例:1.7%
1.7%的重名用户还是挺严重的,希望本文对各位站长对比出本站的用户有所帮助

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