how to insert values into table with auto_increment mysql code example

Example 1: add auto_increment column to existing table mysql

ALTER TABLE `users` ADD `id` INT NOT NULL AUTO_INCREMENT PRIMARY KEY

ALTER TABLE `users` ADD `id` INT NOT NULL AUTO_INCREMENT UNIQUE FIRST

Example 2: how to change the auto increment in existing table mysql

ALTER TABLE tbl_access ADD COLUMN `access_id` int(10) NOT NULL PRIMARY KEY AUTO_INCREMENT FIRST