LOCK TABLES `news_article_category` WRITE;

ALTER TABLE `news_article_category`
ADD COLUMN `slug` VARCHAR(50) NOT NULL AFTER `title`,
ADD INDEX `fk_news_article_category_site1_idx` (`site_id` ASC),
ADD INDEX `idx_slug` (`slug` ASC),
DROP INDEX `fk_news_article_category_site1_idx`;

UNLOCK TABLES;