SQL查询TO JPQL之一

Question

我正在尝试转换此SQL查询：

SELECT *
    FROM event
    WHERE idEvent IN (SELECT idEventfk FROM userevent WHERE absence='1');

进入JPQL：

SELECT e FROM Event e where e.idEvent
IN (SELECT ue.idEventfk FROM userevent ue WHERE ue.absence='1'

但结果正在返回null。对这个错误有什么看法吗？

Answer 1

如果您在Event实体中有相关实体的对象，那么您可以加入它们以获得所需的结果：

select e from Event e join e.userevent ue where ue.absence = '1'

Answer 2

试试这个：

SELECT e.* FROM Event e where e.idEvent
IN (SELECT ue.idEventfk FROM userevent ue WHERE ue.absence='1')

Answer 3

您可以使用EXISTS子句：

SELECT e FROM Event e 
where exists 
  (SELECT ue FROM userevent ue WHERE e.idEvent = ue.idEventfk and ue.absence='1')