Answers for "update auto increment after creating the table in my sql"

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

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

auto increment column in mysql query results

SET @auto_increment=0;
SELECT @auto_increment := @auto_increment+1 AS `No`;