CriteriaBuilder和& CriteriaBuilder.or,或如何? [英] CriteriaBuilder.and & CriteriaBuilder.or, how-to?

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问题描述

我正在尝试更改以下HQL以使用JPA标准:

I'm trying to change the following HQL to use JPA Criteria:

select distinct d from Department d 
left join fetch d.children c 
where d.parent is null 
and (
    d.name like :term 
    or c.name like :term
    ) 
order by d.name

部门有一个 Set<部门> 的孩子。

条件:

CriteriaBuilder cb = getEntityManager().getCriteriaBuilder();
CriteriaQuery<Department> c = cb.createQuery(Department.class);
Root<Department> root = c.from(Department.class);
root.fetch("children", JoinType.LEFT);
Path<Department> children = root.join("children", JoinType.LEFT);
c.orderBy(cb.asc(root.get("name")));
c.distinct(true);
c.where(cb.isNull(root.get("parent")));
String param = "%" + "term" + "%";
cb.and(cb.like(root.<String> get("name"), param));
cb.or(cb.like(children.<String> get("name"), param));

TypedQuery<Department> tq = getEntityManager().createQuery(c);
departments = tq.getResultList();

我知道这可能有点简洁,但是HQL返回24,而Criteria版本为28。认为我没有处理:

I know it can be a bit terse, however, the HQL returns 24 and Criteria version 28. I think I'm not handling:

and (x = y OR z = y)

正确。任何指针将不胜感激。
谢谢。

correctly. Any pointers will be greatly appreciated. Thanks.

推荐答案

这是JPQL查询的where子句:

Here's the where clause of your JPQL query:

where d.parent is null 
and (
    d.name like :term 
    or c.name like :term
    ) 

where子句包含两个谓词:

The where clause contains two predicates:

d.parent is null 

(d.name like :term 
 or c.name like :term)

第二个谓词是包含两个谓词:

The second predicate is an or containing two predicates:

d.name like :term

c.name like :term

因此您的条件查询中需要相同的结构:

So you need the same structure in your criteria query:

Predicate orClause = 
    cb.or(cb.like(root.<String>get("name"), param),
          cb.like(children.<String>get("name"), param));

c.where(cb.isNull(root.get("parent")),
        orClause);

这篇关于CriteriaBuilder和&amp; CriteriaBuilder.or,或如何?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!

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