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：

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)