SQL 分组、拥有和排序 (MySQL)

Question

我有以下 SQL：

select code, distance from places;    

输出如下：

CODE      DISTANCE
106     386.895834130068
80      2116.6747774121 
80      2117.61925131453
106     2563.46708627407

我希望能够只获得一个代码和最近的距离。所以我希望它返回这个：

CODE      DISTANCE
106     386.895834130068
80      2116.6747774121

仍在使用 Distinct 和 Group By。

Answer 1

select `code`, min(distance) as minimal_distance
from places
group by `code`

Answer 2

select code, min(distance) as distance
from places
group by code

这里有 GROUP BY 的手册： http://dev.mysql.com/doc/refman/5.0/en/group-by-functions-and-modifiers.html

教程：

• http://www.tizag.com/mysqlTutorial/mysqlgroupby.php/
• http://www.w3schools.com/sql/sql_groupby.asp

Answer 3

试试这个：

SELECT
  Code,
  MIN(Distance) AS closest_distance
FROM
  your_table
GROUP BY
  Code

Answer 4

select `code`, min(distance) as distance
from places
group by `code`

Answer 5

select code, min(distance) as mindist
from places
group by code