这是我要在jpa中转换的sql语句:
select
id,
act_invalidation_id,
last_modification_date,
title,
case when act_invalidation_id is null then 1 else 0 end as test
from act order by test, last_modification_date desc
实际翻译
Root<Act> act = query.from(Act.class);
builder.selectCase()
.when(builder.isNull(actRoot.get("actInvalidation")), 1)
.otherwise(0).as(Integer.class);
Expression<?> actInvalidationPath = actRoot.get("actInvalidation");
Order byInvalidationOrder = builder.asc(actInvalidationPath);
Path<Date> publicationDate = actRoot.get("metadata").get("publicationDate");
Order byLastModificationDate = builder.desc(publicationDate);
query.select(act).orderBy(byInvalidationOrder, byLastModificationDate);
entityManager.createQuery(query).getResultList();
我尝试创建一个Integer类型的临时列(名为test),并按此列排序,然后按lastmodificationdate排序。新列的内容由actInvalidation字段的值确定。
简而言之:如何创建一个具有整数值的临时列,然后在jpa中按此临时列排序?
谢谢
答案 0 :(得分:1)
我没有对此进行测试,但它应该像这样工作:
Root<Act> act = query.from(Act.class);
Expression<?> test = builder.selectCase()
.when(builder.isNull(actRoot.get("actInvalidation")), 1)
.otherwise(0).as(Integer.class);
Expression<?> actInvalidationPath = actRoot.get("actInvalidation");
Order byInvalidationOrder = builder.asc(actInvalidationPath);
Path<Date> publicationDate = actRoot.get("metadata").get("publicationDate");
Order byLastModificationDate = builder.desc(publicationDate);
Order byTest = builder.asc(test);
query.select(act).orderBy(byTest, byInvalidationOrder, byLastModificationDate);
entityManager.createQuery(query).getResultList();