MySQL多个IN条件可以使用同一表进行子查询

Question

我有多个IN条件与子查询。

SELECT
    S.name,
    S.email
FROM something S
WHERE 
    1 NOT IN (SELECT id FROM tags WHERE somethingId = S.id)
    AND 2 NOT IN (SELECT id FROM tags WHERE somethingId = S.id)
    AND 3 NOT IN (SELECT id FROM tags WHERE somethingId = S.id)

也许有更好的解决方案？就像是：

    (1, 2, 3) NOT IN (SELECT id FROM tags WHERE somethingId = S.id)

Answer 1

重新编写以NOT EXISTS代替使用。即，当某标签中没有某行的somethingId等于s.id并且id为1、2或3时，即从S返回。

SELECT
    S.name,
    S.email
FROM something S
WHERE NOT EXISTS (SELECT 1 FROM tags WHERE id in (1, 2, 3) and somethingId = S.id)

也是NOT EXISTS“ null-safe”。（NOT IN (select returning a null)将完全不返回任何行。）