MySQL中的CONCAT函数使用教程
时间：2021-02-10 14:50:36|栏目：Mysql|点击： 次
使用MySQL CONCAT()函数将两个字符串连接起来，形成一个单一的字符串。试试下面的例子：
mysql> SELECT CONCAT('FIRST ', 'SECOND');
+----------------------------+
| CONCAT('FIRST ', 'SECOND') |
+----------------------------+
| FIRST SECOND |
+----------------------------+
1 row in set (0.00 sec)
了解CONCAT函数更详细，考虑EMPLOYEE_TBL表具有以下记录：
mysql> SELECT * FROM employee_tbl; +------+------+------------+--------------------+ | id | name | work_date | daily_typing_pages | +------+------+------------+--------------------+ | 1 | John | 2007-01-24 | 250 | | 2 | Ram | 2007-05-27 | 220 | | 3 | Jack | 2007-05-06 | 170 | | 3 | Jack | 2007-04-06 | 100 | | 4 | Jill | 2007-04-06 | 220 | | 5 | Zara | 2007-06-06 | 300 | | 5 | Zara | 2007-02-06 | 350 | +------+------+------------+--------------------+ 7 rows in set (0.00 sec)
可以用以下命令连结上表中的name和ID：
mysql> SELECT CONCAT(id, name, work_date) -> FROM employee_tbl; +-----------------------------+ | CONCAT(id, name, work_date) | +-----------------------------+ | 1John2007-01-24 | | 2Ram2007-05-27 | | 3Jack2007-05-06 | | 3Jack2007-04-06 | | 4Jill2007-04-06 | | 5Zara2007-06-06 | | 5Zara2007-02-06 | +-----------------------------+ 7 rows in set (0.00 sec)
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