db error 1064

[anestetic]

Database error in vBulletin 3.6.8:

Invalid SQL:
ALTER TABLE user DROP COLUMN 'casino_cash';

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 ''casino_cash'' at line 1
Error Number : 1064
Date         : Monday, November 19th 2007 @ 02:55:27 PM
Script       : http://xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/plugin.php?do=productkill
Referrer     : http://xxxxxxxxxxxxxxxxxxxxxxxx/plugin.php?do=productdelete&productid=casino&s=
IP Address   :xxx.xx.xx.xxxx
Username     : AnesTetiC
Classname    : vb_database

please help me