fix for single word identifiers with no spaces that need protecting in _protect_identifiers()
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index a164552..9dc6976 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -452,7 +452,7 @@
 

 		// This function may get "item1 item2" as a string, and so

 		// we may need "`item1` `item2`" and not "`item1 item2`"

-		if (strpos($item, ' ') !== FALSE)

+		if (ctype_alnum($item) !== FALSE)

 		{

 			// This function may get "field >= 1", and need it to return "`field` >= 1"

 			if ($first_word_only === TRUE)

@@ -462,6 +462,10 @@
 

 			$item = preg_replace('/(^|\s|\()([\w\d\-\_]+?)(\s|\)|$)/iS', '$1`$2`$3', $item);

 		}

+		else

+		{

+			return "`{$item}`";

+		}

 

 		$exceptions = array('AS', '/', '-', '%', '+', '*');