Fix issue #1483
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index f3e75cb..4c70ccc 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -451,7 +451,7 @@
 		}
 
 		// If the escape value was not set will will base it on the global setting
-		$escape = $this->_protect_identifiers;
+		is_bool($escape) OR $escape = $this->_protect_identifiers;
 
 		foreach ($key as $k => $v)
 		{