ALTER TABLE `table_name` ADD COLUMN `id` INT AUTO_INCREMENT UNIQUE FIRST;
add primary key with auto increment to existing table column in mysql
#ALTER table user_info MODIFY id int(15) PRIMARY KEY AUTO_INCREMENT;
#ALTER table user_info drop PRIMARY KEY;
ALTER TABLE tbl_access ADD COLUMN `access_id` int(10) NOT NULL PRIMARY KEY AUTO_INCREMENT FIRST
CREATE TABLE IF NOT EXISTS blog_users (
id INT NOT NULL AUTO_INCREMENT,
email VARCHAR(255) NOT NULL,
password VARCHAR(255) NOT NULL,
PRIMARY KEY (id)
)