在第一个表上加入两个带条件的表

Question

我想将这两个组合成一个SELECT语句：

SELECT * 
FROM activegroupmodel 
WHERE groupID = ? 
ORDER BY groupModelID DESC 
LIMIT 1

SELECT * 
FROM model 
WHERE modelID = ?

正如您从第一个组中看到的那样，ID不是pk，我想要该表中的最新模型。 我试过这个，但显然没有用：

SELECT * 
FROM activegroupmodel as a 
WHERE a.groupID = ? 
ORDER BY a.groupModelID DESC 
LIMIT 1 
INNER JOIN model as m ON a.modelID = m.modelID

我已经通过JOIN阅读了一堆问题，但没有一个问题符合我的问题。 谁知道我怎么解决这个问题？ 最好的问候约翰

Answer 1

将你的JOIN放在WHERE条件之前，如下所示：

SELECT * 
FROM activegroupmodel as a
INNER JOIN model as m ON a.modelID = m.modelID
WHERE a.groupID = ? 
ORDER BY a.groupModelID DESC 
LIMIT 1 

Answer 2

SELECT * 
FROM activegroupmodel as a 
INNER JOIN model as m ON a.modelID = m.modelID
WHERE a.groupID = ? 
ORDER BY a.groupModelID DESC 
LIMIT 1 

Answer 3

正确的连接语句应为

SELECT * 
FROM activegroupmodel as a 
INNER JOIN model as m ON a.modelID = m.modelID
WHERE a.groupID = ? 
ORDER BY a.groupModelID DESC 
LIMIT 1 

Answer 4

试试这个

SELECT * 
FROM activegroupmodel as a 
INNER JOIN model as m ON a.modelID = m.modelID
WHERE a.groupID = ? 
ORDER BY a.groupModelID DESC 
LIMIT 1