JPA标准查询和子查询 [英] JPA criteria query with subquery

问题描述

我想知道是否可以使用jpa 2.0条件api表达以下查询.

I was wondering if it was possible to express the following query with jpa 2.0 criteria api.

simple_table:
user_name(varchar),
bytes_total(bigint),
time_total(bigint)

>select
   user_name, 
   sum(bytes_total),
   sum(bytes_total) * 100 / (select sum(bytes_total) from simple_table),
   sum(time_total),
   sum(time_total) * 100 / (select sum(time_total) from simple_table)
from simple_table
group by user_name

除了两个子查询之外，我都能正常工作.我想知道这是否可能.谢谢.

I have everything working except for the two sub-queries. I would like to know whether or not this is possible. Thanks.

推荐答案

无法完成.子查询不能在SELECT子句中使用. JPQL查询中有相同的限制.在JPA 2.0规范中，它表示为:

That cannot be done. Subqueries cannot be used in SELECT clause. Same limitation is in JPQL queries. In JPA 2.0 specification this is expressed as follows:

子查询可以在WHERE和HAVING子句中使用.

Subqueries may be used in the WHERE and HAVING clause.

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