可以借助一个示例进行说明,在该示例中,我们在名为“ employee_data”的表中创建虚拟生成的列。众所周知,可以在使用或不使用关键字'virtual'的情况下生成虚拟生成的列。
mysql> Create table employee_data(ID INT AUTO_INCREMENT PRIMARY KEY, First_name VARCHAR(50) NOT NULL, Last_name VARCHAR(50) NOT NULL, FULL_NAME VARCHAR(90) GENERATED ALWAYS AS(CONCAT(First_name,'',Last_name))); mysql> DESCRIBE employee_data; +------------+-------------+------+-----+---------+-------------------+ | Field | Type | Null | Key | Default | Extra | +------------+-------------+------+-----+---------+-------------------+ | ID | int(11) | NO | PRI | NULL | auto_increment | | First_name | varchar(50) | NO | | NULL | | | Last_name | varchar(50) | NO | | NULL | | | FULL_NAME | varchar(90) | YES | | NULL | VIRTUAL GENERATED | +------------+-------------+------+-----+---------+-------------------+ 4 rows in set (0.00 sec) mysql> INSERT INTO employee_data(first_name, Last_name) values('Yashpal','Sharma'); mysql> INSERT INTO employee_data(first_name, Last_name) values('Krishan','Kumar'); mysql> INSERT INTO employee_data(first_name, Last_name) values('Rakesh','Arora'); mysql> Select * from employee_data; +----+------------+-----------+----------------+ | ID | First_name | Last_name | FULL_NAME | +----+------------+-----------+----------------+ | 1 | Yashpal | Sharma | Yashpal Sharma | | 2 | Krishan | Kumar | Krishan Kumar | | 3 | Rakesh | Arora | Rakesh Arora | +----+------------+-----------+----------------+ 3 rows in set (0.00 sec)