可以通過(guò)一個(gè)示例進(jìn)行說(shuō)明，在該示例中，我們?cè)诿麨椤癳mployee_data”的表中創(chuàng)建一個(gè)虛擬生成的列。我們知道，可以使用或不使用關(guān)鍵字“virtual”來(lái)生成虛擬生成列。
示例
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)));
Query OK, 0 rows affected (0.55 sec)
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');
Query OK, 1 row affected (0.09 sec)
mysql> INSERT INTO employee_data(first_name, Last_name) values('Krishan','Kumar');
Query OK, 1 row affected (0.09 sec)
mysql> INSERT INTO employee_data(first_name, Last_name) values('Rakesh','Arora');
Query OK, 1 row affected (0.08 sec)
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)
登錄后復(fù)制
以上就是MySQL 虛擬生成列如何與內(nèi)置函數(shù)一起使用？的詳細(xì)內(nèi)容，更多請(qǐng)關(guān)注www.92cms.cn其它相關(guān)文章！
