SQL - 查询某一字段值相同而另外一字段值最大的记录

时间 2019-12-14

标签 sql 查询某一字段相同另外最大记录栏目 SQL 繁體版

原文原文链接

有时须要以某一字段做为分组，筛选每一组的另外一字段值最大（或最小）的记录。例如，有以下表 app，存储了 app 的 ID、名称、版本号等信息。如今要筛选出每一个 app 版本最大的记录。app

方法一spa

SELECT a.* FROM app a 
WHERE a.app_version = (SELECT MAX(b.app_version) FROM app b WHERE b.app_name = a.app_name) 
ORDER BY a.app_name;

方法二code

SELECT a.* FROM app a
WHERE NOT EXISTS(SELECT 1 FROM app b WHERE b.app_name = a.app_name AND b.app_version > a.app_version)
ORDER BY a.app_name;

方法三blog

SELECT a.* 
FROM app a, (SELECT app_name, MAX(app_version) AS app_version FROM app GROUP BY app_name) b
WHERE a.app_name = b.app_name
AND a.app_version = b.app_version
ORDER BY a.app_name;

方法四io

SELECT a.* 
FROM app a INNER JOIN (SELECT app_name, MAX(app_version) AS app_version FROM app GROUP BY app_name) b
ON a.app_name = b.app_name
AND a.app_version = b.app_version
ORDER BY a.app_name;