关系代数与 SQL [关闭]

Question

我正在尝试从关系代数转换为 SQL，但我不知道如何进行双重 INNER JOIN。

π did ((π cid ((σ (name='Linda')(Driver)) ⨝ (Res))) ⨝ (Res)) - π did (σ (name='Linda')(Driver))

应该是这样的：

SELECT Res.did
FROM (SELECT Res.cid
FROM Driver INNER JOIN Res ON Driver.did = Res.did
WHERE name = 'Linda') INNER JOIN Res
EXCEPT
SELECT did
FROM Driver
WHERE name = 'Linda'