The generated columns are also known as virtual or computed columns. The values of a generated column are computed from an expression included in the column definition. There are two types of generated columns:
Virtual generated columns are more useful than stored generated columns because a virtual column does not take any storage space. You can simulate the behavior of stored generated columns using triggers.
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...