MySQL 8 Cookbook

How to do it...

Suppose your application is using full_name as concat('first_name', ' ', 'last_name') while retrieving the data from the employees table; instead of using the expression, you can use a virtual column, which calculates full_name on the fly. You can add another column followed by the expression:

mysql> CREATE TABLE `employees` (  `emp_no` int(11) NOT NULL,  `birth_date` date NOT NULL,  `first_name` varchar(14) NOT NULL,  `last_name` varchar(16) NOT NULL,  `gender` enum('M','F') NOT NULL,  `hire_date` date NOT NULL,  `full_name` VARCHAR(30) AS (CONCAT(first_name,' ',last_name)),  PRIMARY KEY (`emp_no`),  KEY `name` (`first_name`,`last_name`)) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

Note that you should modify the insert statement according ...