ALTER TABLE `categories` ADD COLUMN `slug` VARCHAR(100) NOT NULL AFTER `name`;
UPDATE `categories` set `slug` = `name`;
ALTER TABLE `categories` ADD UNIQUE (`slug`);

ALTER TABLE `groups` ADD COLUMN `slug` VARCHAR(100) NOT NULL AFTER `name`;
UPDATE `groups` set `slug` = `name`;
ALTER TABLE `groups` ADD UNIQUE (`slug`);

ALTER TABLE `companies` ADD COLUMN `slug` VARCHAR(255) NOT NULL AFTER `name`;
UPDATE `companies` set `slug` = `name`;
ALTER TABLE `companies` ADD UNIQUE (`slug`);
