如何使用JPA編寫復雜的聯接查詢

Question

如何用JPA編寫這種復雜的聯接查詢，我在下面指出的某些語法不適用於JPA。 我用它們來演示sql查詢應建立的方式，對此感到抱歉。

SELECT Result1.name1, Result1.count1, Result2.name2, Result2.count2 FROM (
    SELECT 
        taskOne.user.name AS name1,
        COUNT(taskOne.taskId) AS count1
    FROM
        Task AS taskOne
    INNER JOIN
        taskOne.defect AS defectOne
    WHERE (
        defectOne.defId = taskOne.defect.defId
        AND
        taskOne.taskCategory.tcaId = 1
    )
    GROUP BY
        taskOne.user.usId
) AS Result1
FULL JOIN (
    SELECT
        taskTwo.user.name AS name2,
        COUNT(taskTwo.taskId) AS count2
    FROM Task AS taskTwo
    INNER JOIN taskTwo.defect AS defectTwo
    WHERE (
        defectTwo.defId = taskTwo.defect.defId
        AND
        taskTwo.taskCategory.tcaId = 2
    )
    GROUP BY taskTwo.user.usId
)
AS Result12
WHERE Result1.name1 = Result12.name2

Answer 1

JPQL是選擇對象所需要的。 您的查詢似乎異常復雜，我建議您使用本機SQL查詢或對其進行簡化。

JPQL不支持from子句中的子選擇。