MySQL中的CONCAT函数使用教程
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2024-02-29 15:56:52
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 '...
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)