MySQL MIN 函数

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  MIN 函数

  MySQL MIN函数用于在记录集中找出最小值的记录。要了解MIN函数，请考虑一个employee_tbl表，该表具有以下记录-

  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)
  

  现在，假设基于上表您要获取daily_typing_pages的最小值，那么您可以使用以下命令简单地做到这一点：

  mysql> SELECT MIN(daily_typing_pages)
     -> FROM employee_tbl;
  +-------------------------+
  | MIN(daily_typing_pages) |
  +-------------------------+
  |          100            |
  +-------------------------+
  1 row in set (0.00 sec)

  您可以使用GROUP BY子句找到每个名称具有最小值的所有记录，如下所示-

  mysql>SELECT id, name, MIN(daily_typing_pages)
      -> FROM employee_tbl GROUP BY name;
  +------+------+-------------------------+
  |  id  | name | MIN(daily_typing_pages) |
  +------+------+-------------------------+
  |   3  | Jack |           100           |
  |   4  | Jill |           220           |
  |   1  | John |           250           |
  |   2  | Ram  |           220           |
  |   5  | Zara |           300           |
  +------+------+-------------------------+
  5 rows in set (0.00 sec)

  您也可以将MIN 函数和MAX 函数一起使用以找出最大值。尝试以下示例-

  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)