Question

我需要进行类似的查询：

SELECT DISTINCT Carta_ID
FROM Carta_Alarme
INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
WHERE (
YEAR( Alarme.dtOcorrencia ) = 2011
) NOT
IN (

SELECT DISTINCT Carta_ID
FROM Carta_Alarme
INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
WHERE (
YEAR( Alarme.dtOcorrencia ) = 2012
)
)

首先选择的结果是（1,5,6）。 “NOT IN”之后的另一个选择的结果是（1,2,3,4,5），但总查询的结果是（1,2,3,4,5），我只需要（6）。

所以我需要的是这个选择之间的区别，我得到的是INTERSECT

Answer 1

SELECT DISTINCT Carta_ID
FROM Carta_Alarme
INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
WHERE (
YEAR( Alarme.dtOcorrencia ) = 2011
) AND Carta_ID NOT
IN (

SELECT DISTINCT Carta_ID
FROM Carta_Alarme
INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
WHERE (
YEAR( Alarme.dtOcorrencia ) = 2012
)
)

Answer 2

SELECT Carta_ID
FROM Carta_Alarme
INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
GROUP BY Carta_ID
HAVING sum(YEAR(Alarme.dtOcorrencia) = 2011) > 0 
   and sum(YEAR(Alarme.dtOcorrencia) = 2012) = 0

Answer 3

SQL Fiddle

这实际上是minus set operation

SELECT DISTINCT ca.Carta_ID
FROM Carta_Alarme ca
INNER JOIN Alarme a ON ca.Alarme_ID = a.ID
left join (SELECT DISTINCT Carta_ID
           FROM Carta_Alarme
           INNER JOIN Alarme ON Carta_Alarme.Alarme_ID = Alarme.ID
           WHERE YEAR( Alarme.dtOcorrencia ) = 2012) ca2 on ca2.Carta_id = ca.Carta_id
WHERE YEAR( a.dtOcorrencia ) = 2011
      and ca2.Carta_id is null

Mysql查询除外

3 个答案: