這篇文章主要介紹了MySQL中MIN()函數的使用教程,是MySQL入門學習中的基礎知識,需要的朋友可以參考下
MySQL的MIN函數是用來找出一個記錄集最小值的記錄。
要了解MIN函數考慮的EMPLOYEE_TBL表具有以下記錄:
- 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)
現在假設上面的表的基礎上想要取daily_typing_pages的最小值,那么可以這樣做,簡單地使用下面的命令:
- mysql> SELECT MIN(daily_typing_pages)
- -> FROM employee_tbl;
- +-------------------------+
- | MIN(daily_typing_pages) |
- +-------------------------+
- | 100 |
- +-------------------------+
- 1 row in set (0.00 sec)
可以找到所有記錄的最小值按名字使用GROUP BY子句如下:
- mysql> id, name, work_date, MIN(daily_typing_pages)
- -> FROM employee_tbl GROUP BY name;
- +------+------+------------+-------------------------+
- | id | name | work_date | MIN(daily_typing_pages) |
- +------+------+------------+-------------------------+
- | 3 | Jack | 2007-05-06 | 100 |
- | 4 | Jill | 2007-04-06 | 220 |
- | 1 | John | 2007-01-24 | 250 |
- | 2 | Ram | 2007-05-27 | 220 |
- | 5 | Zara | 2007-06-06 | 300 |
- +------+------+------------+-------------------------+
- 5 rows in set (0.00 sec)
您可以使用MIN函數和MAX函數一起,查找最小值。試試下面的例子:
- mysql> SELECT MIN(daily_typing_pages) least, MAX(daily_typing_pages) max
- -> FROM employee_tbl;
- +-------+------+
- | least | max |
- +-------+------+
- | 100 | 350 |
- +-------+------+
- 1 row in set (0.01 sec)
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