fixed bug #3260 tightened type checking before outputting MySQL field as NULL
diff --git a/system/database/drivers/mysql/mysql_utility.php b/system/database/drivers/mysql/mysql_utility.php
index c24a008..3c5b940 100644
--- a/system/database/drivers/mysql/mysql_utility.php
+++ b/system/database/drivers/mysql/mysql_utility.php
@@ -179,7 +179,7 @@
 					$v = str_replace('\\\t', '\t',	$v);

 

 					// Is the value NULL?

-					if ($v == NULL)

+					if ($v === NULL)

 					{

 						$val_str .= 'NULL';

 					}