How to create virtual column using MySQL SELECT?

To create a virtual column using a MySQL SELECT statement, you can use the AS keyword to assign a name to an expression in the SELECT statement. For example:

Example of creating virtual column using MySQL SELECT in PHP

SELECT column1, column2, column1 + column2 AS virtual_column
FROM table_name;

This would select column1, column2, and a virtual column named virtual_column that is the result of the expression column1 + column2.

It's important to note that the virtual column is not physically stored in the table; it's only available for the specific SELECT statement.

Also, starting from MySQL 5.7, MySQL supports generated (computed) columns. By default, they are VIRTUAL, but you can specify STORED to persist the value on disk. Note that computed columns cannot be updated directly; you must update the base columns they depend on. You can create a stored computed column like this:

Example of creating a stored computed column in MySQL 5.7 and above

ALTER TABLE table_name ADD COLUMN virtual_column AS (column1 + column2) STORED;