Merge branch 2.1-stable into develop
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 5d0a2ae..3b45bba 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -1985,7 +1985,7 @@
 		if (strpos($table, ' ') !== FALSE)
 		{
 			// if the alias is written with the AS keyword, remove it
-			$table = preg_replace('/ AS /i', ' ', $table);
+			$table = preg_replace('/\s+AS\s+/i', ' ', $table);
 
 			// Grab the alias
 			$table = trim(strrchr($table, ' '));