mysql> create table v(a int, b int as(a*2));
Query OK, 0 rows affected (0.20 sec)
mysql> insert into v(a) values(1);
Query OK, 1 row affected (0.03 sec)
mysql> select * from v;
+------+------+
| a | b |
+------+------+
| 1 | 2 ...
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