require("connect.php");
$v=explode(chr(13),$_POST['data']);
$a = '';
foreach($v as $values)
{
$a=trim($values);
if($a!=NULL)
{
$result=mysql_query("select * from baidublog where user='$a'");if(mysql_num_rows($result)==0)
{
mysql_query("insert into baidublog(user) values ('$a');");
}}
}
mysql挂了,很可能是你内存参数配置不合理导致溢出所致,和你php没关系