Question

在mysql中我有这两个表：

**Seasons**
id
number
current

**Episodes**
id
number
season_id
other_info

我想从Episodes得到一整行，Seasons的联接行全部基于两个表的最大number值。

例如，如果我有第1季，第2季，我想从最近的季节获得最新一集。

我从这个问题开始：

SELECT e.id as episode_id, s.id as season_id, MAX(s.number) AS season_number, MAX(e.number) AS episode_number, e.other_info
FROM (episodes AS e)
JOIN seasons AS s ON e.season_id=s.id
WHERE s.current =  1

它有点工作，但它显示错误的other_info值。我理解这是因为MAX()对行进行了分组，但其他值有点随机，所以我认为它只显示了第一行可用的other_info。

环顾四周，我发现了我认为可行的这个，但它并没有：

SELECT e.id as episode_id, s.id as season_id, MAX(s.number) AS season_number, MAX(e.number) AS episode_number, e.other_info
FROM (episodes AS e)
JOIN seasons AS s ON e.season_id=s.id
WHERE s.current =  1 AND
e.number = (select max(sube.number) from episodes sube);

在这种情况下，我只获取所有NULL值。

Answer 1

我认为这会对你有所帮助：

SELECT seasons.*, episodes.* 
FROM episodes
INNER JOIN seasons ON episodes.season_id = seasons.id
ORDER BY seasons.number DESC ,episodes.number DESC 
limit 0,1

根据最大值获取包含连接的完整行

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