Uncaught Exception: SqlException

Message:
invalid query:- SELECT fm.*, u.username, u.id as sorturl_userid FROM `file_management` fm ,users u WHERE u.id=fm.user_id AND fm.type=0 and u.private_url='http:' Limit -4, 4
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 '-4, 4' at line 1
Created in file /home/streamup/public_html/GL/lib/database/SqlDatabaseManager.class.php on line 148.

Stack Trace:
#0 /home/streamup/public_html/appcode/datamanager/FileManagementDataManager.class.php(571): SqlDatabaseManager->executeQuery('SELECT fm.*, u....')
#1 /home/streamup/public_html/protected/controller/home.php(273): FileManagementDataManager->getUserFileListBySortURL('http:', 'getridtattoo.pl...')
#2 [internal function]: home->profile('http:', 'getridtattoo.pl...', '')
#3 /home/streamup/public_html/GL/lib/RegisterCallback.class.php(8): call_user_func_array(Array, Array)
#4 /home/streamup/public_html/GL/lib/Application.class.php(47): RegisterCallback::register(Object(home), 'profile', Array)
#5 /home/streamup/public_html/index.php(14): Application::run(Object(HttpRequest))
#6 {main}
5.
In file /home/streamup/public_html/appcode/datamanager/FileManagementDataManager.class.php line 571.
Method: SqlDatabaseManager->executeQuery([$query FILTERED])
4.
In file /home/streamup/public_html/protected/controller/home.php line 273.
Method: FileManagementDataManager->getUserFileListBySortURL([$sorturl FILTERED], [$page FILTERED])
3.
In file unknown line unknown.
Method: home->profile([$sorturl FILTERED], [$paged FILTERED], '')
2.
In file /home/streamup/public_html/GL/lib/RegisterCallback.class.php line 8.
Method: call_user_func_array([$function_name FILTERED], [$parameters FILTERED])
1.
In file /home/streamup/public_html/GL/lib/Application.class.php line 47.
Method: RegisterCallback::register([$class FILTERED], [$funcName FILTERED], [$args FILTERED])
0.
In file /home/streamup/public_html/index.php line 14.
Method: Application::run([$request FILTERED])