WordPress database error: [Duplicate key name 'quesiton_id']
ALTER TABLE wp_watu_answer ADD INDEX `quesiton_id` (`question_id`);

WordPress database error: [Duplicate key name 'quiz_and_criteria']
ALTER TABLE wp_watu_grading ADD INDEX `quiz_and_criteria` (`exam_id`, `gfrom`, `gto`);

WordPress database error: [Duplicate key name 'name']
ALTER TABLE wp_watu_master ADD INDEX `name` (`name`);

WordPress database error: [Duplicate key name 'exam_id']
ALTER TABLE wp_watu_question ADD INDEX `exam_id` (`exam_id`);

WordPress database error: [Duplicate key name 'cat_id']
ALTER TABLE wp_watu_question ADD INDEX `cat_id` (`cat_id`);

WordPress database error: [Duplicate key name 'exam_user']
ALTER TABLE wp_watu_takings ADD INDEX `exam_user` (`exam_id`, `user_id`);