ارجو منكم المساعدة في تفسير

السلام عليكم

ارجو منكم المساعدة في تفسير الرسائل التاليه
، وكيفية ايقافها وعلاج المشكلة سابقا تم الطلب مني عمل صيانه وقمنا بذلك ، توقفت فتره ثم عادت بهذه الطريقه ، ولكم جزيل الشكر
Database error in vBulletin :

mysql_connect(): Can't connect to local MySQL server through socket
'/var/lib/mysql/mysql.sock' (2)
/usr/local/psa/home/vhosts/alaws2006.com/httpdocs/vb/includes/class_core.php
on line 271

MySQL Error :
Error Number :
Date : Sunday, February 11th 2007 @ 07:24:11 PM
Script : http://alaws2006.com/vb/forumdisplay.php?f=32
Referrer : http://alaws2006.com/vb/forumdisplay.php?f=30
IP Address : 10.20.30.8
Username :
Classname : vb_database

والثانيه
Database error in vBulletin 3.6.2:

Invalid SQL:

SELECT posts AS postcount, userid, username
FROM user AS user
ORDER BY postcount DESC LIMIT 10;

MySQL Error : Lost connection to MySQL server during query
Error Number : 2013
Date : Sunday, February 11th 2007 @ 07:24:10 PM
Script : http://alaws2006.com/vb/
Referrer :
IP Address : 83.244.34.222
Username : علمك سلاحك
Classname : vb_database

والثالثه

Database error in vBulletin 3.6.2:

Invalid SQL:
SELECT COUNT(threadid) AS total FROM thread WHERE postuserid=;

MySQL Error : You have an error in your SQL syntax; check the manual
that corresponds to your MySQL server version for the right syntax to
use near '' at line 1
Error Number : 1064
Date : Sunday, February 11th 2007 @ 08:21:40 PM
Script : http://www.alaws2006.com/vb/showthre...?t=5363&page=2
Referrer : http://www.alaws2006.com/vb/showthread.php?t=5363
IP Address : 213.6.240.47
Username : fadmad
Classname : vb_database

وايضا

Database error in vBulletin 3.6.2:

Invalid SQL:
SELECT userid, joindate, options, username, opentag, closetag, posts
FROM user as user
LEFT JOIN usergroup as usergroup ON(user.usergroupid =
usergroup.usergroupid)
ORDER BY joindate;

MySQL Error : Lost connection to MySQL server during query
Error Number : 2013
Date : Sunday, February 11th 2007 @ 07:24:10 PM
Script : http://alaws2006.com/vb/register.php?
Referrer : http://alaws2006.com/vb/showthread.php?t=4431
IP Address : 213.6.150.152
Username : غير مسجل
Classname : vb_database