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MySQL中的CONCAT函数使用教程

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:

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1234567mysql> 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:

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12345678910111213mysql> 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:

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1234567891011121314mysql> 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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