Merge branch 'F6944-sql-hint-double-comma' into 'master'

F6944 - Add double comma SQL Hint - refs #6944, closes #6944

See merge request !101

extension/qfq/qfq/database/Database.php

@@ -323,6 +323,11 @@ class Database {
             $msg .= "HINT: Maybe the tables after 'FROM' should be enclosed by '()' \n";
         }
 
+        // Check for double comma
+        if (stripos($errorMsg, 'the right syntax to use near') && preg_match('/,[ ]*,/', $sql)) {
+            $msg .= "HINT: There seems to be a double comma in your query.\n";
+        }
+
         return $msg;
     }