Comments - Generated (Virtual and Persistent/Stored) Columns

"A virtual column is a column in a table that has its value automatically calculated using either a deterministic expression, or the values of other fields in the table."

This seems to say that it is possible to use an expression that does not refer to other fields in the tables. However, to my knowledge, such an expression is either not deterministic or constant. In both cases it is rejected by MariaDB.

By the way, I don't understand why constant expressions could not be accepted.

Thanks, the wording is incorrect and will be changed. I'm also unsure as to why constants are not accepted!

By the way, I don't understand why constant expressions could not be accepted.

They apparently work in 10.1.6:

ALTER TABLE `z_test` ADD `Const` INT(5)  AS (`ID` + 1) PERSISTENT AFTER `ID`;

MariaDB [EcoReality]> SELECT ID, Const from z_test;
+----+-------+
| ID | Const |
+----+-------+
|  1 |     2 |
|  2 |     3 |
|  3 |     4 |
|  4 |     5 |
+----+-------+
4 rows in set (0.00 sec)

(I don't understand why this forum doesn't allow a bit of prettifying HTML...)-:

The editing help page gives details on formatting. I've tidied up your post above - there's lots you can do, just not HTML :)