db->dbprefix; if ($this->db->dbdriver == 'postgre') { $this->db->query(' CREATE UNIQUE INDEX "'.$prefix.'users_username_idx" ON "'.$prefix.'users" ("username") '); } else { $this->db->query(' ALTER TABLE `'.$prefix.'users` ADD UNIQUE `username` (`username`); '); } } public function down() { $prefix = $this->db->dbprefix; if ($this->db->dbdriver == 'postgre') { $this->db->query('DROP INDEX "'.$prefix.'users_username_idx"'); } else { $this->db->query(" ALTER TABLE `'.$prefix.'users` DROP INDEX `username`; "); } } }