SQL CONCAT函数

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SQL CONCAT函数实例代码教程 - SQL CONCAT函数用于将两个字符串连接起来，形成一个单一的字符串。

SQL CONCAT函数用于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：

SQL> SELECT CONCAT('FIRST ', 'SECOND');+----------------------------+| CONCAT('FIRST ', 'SECOND') |+----------------------------+| FIRST SECOND               |+----------------------------+1 row in set (0.00 sec)

想要更详细了解CONCAT函数，考虑EMPLOYEE_TBL的表具有以下记录：

SQL> 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)

现在，假设根据上述表要连接名员工ID和work_date，那么你可以使用下面的命令：

SQL> 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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