我们如何在带有CREATE TABLE语句的MySQL表中具有多个virtuals GENERATED COLUMNS?
很可能在MySQL表中添加多个虚拟生成的列。可以通过以下示例进行说明-
示例
mysql> Create table profit(cost int, price int, profit int AS (price-cost), price_revised int AS (price-2)); mysql> Describe profit; +---------------+---------+------+-----+---------+-------------------+ | Field | Type | Null | Key | Default | Extra | +---------------+---------+------+-----+---------+-------------------+ | cost | int(11) | YES | | NULL | | | price | int(11) | YES | | NULL | | | profit | int(11) | YES | | NULL | VIRTUAL GENERATED | | price_revised | int(11) | YES | | NULL | VIRTUAL GENERATED | +---------------+---------+------+-----+---------+-------------------+ 4 rows in set (0.00 sec) mysql> Insert into profit(Cost, Price) values(100,110); mysql> Insert into profit(Cost, Price) values(200,220); mysql> Select * from profit; +------+-------+--------+---------------+ | cost | price | profit | price_revised | +------+-------+--------+---------------+ | 100 | 110 | 10 | 108 | | 200 | 220 | 20 | 218 | +------+-------+--------+---------------+ 2 rows in set (0.00 sec)