Add multi-variant test sets

administrator/components/com_testquestions/sql/updates/mysql/1.34.0.sql

@@ -0,0 +1,7 @@
+ALTER TABLE `#__testquestions_sets`
+  ADD COLUMN `parent_id` int unsigned NOT NULL DEFAULT 0 AFTER `id`,
+  ADD COLUMN `set_type` varchar(12) NOT NULL DEFAULT 'ordinary' AFTER `parent_id`;
+
+UPDATE `#__testquestions_sets`
+SET `set_type` = 'ordinary'
+WHERE `set_type` = '' OR `set_type` IS NULL;