Add __call to query builder

sys/db/query_builder.php

@@ -920,6 +920,28 @@ class Query_Builder {
 
 	// --------------------------------------------------------------------------
 
+	/**
+	 * Calls a function further down the inheritence chain
+	 *
+	 * @param string $name
+	 * @param array $params
+	 * @return mixed
+	 */
+	public function __call($name, $params)
+	{
+		if ( ! empty($this->db->$name))
+		{
+			if (is_callable($this->db->$name))
+			{
+				return call_user_func_array(array($this->db, $name), $params);
+			}
+		}
+
+		return NULL;
+	}	
+	
+	// --------------------------------------------------------------------------
+	
 	/**
 	 * Clear out the class variables, so the next query can be run
 	 */

tests/databases/firebird-qb.php

@@ -142,6 +142,8 @@ class FirebirdQBTest extends UnitTestCase {
 			->get();
 		
 		$this->assertTrue(is_resource($query));
+
+		<pre><?= print_r($this->db->fetchAll(), TRUE) ?></pre>
 	}
 	
 	/*function TestGroupBy()