from 子句中的 JPA/hibernate 子查询答案

【问题标题】：JPA/hibernate subquery in from clausefrom 子句中的 JPA/hibernate 子查询
【发布时间】：2011-11-08 07:12:39
【问题描述】：

我们使用 JPA 和 hibernate 作为提供者，我们有一个查询，它在 FROM 子句中包含一个带有子查询的连接，但我们收到以下错误：

org.hibernate.hql.ast.QuerySyntaxException：意外令牌：（附近第 1 行，第 75 列 [SELECT sd FROM com.hp.amber.datamodel.entities.analysis.SnapshotDates sd，（选择 max(x.changeDate) maxChangeDate, x.viewId, x.state FROM com.hp.amber.datamodel.entities.analysis.SnapshotDates x WHERE x.changeDate<:date and x.viewid in x.state=":state" group sd2 sd.viewid="sd2.viewId" sd.state=":state" sd.changedate="sd2.maxChangeDate]</p">

这是查询：

SELECT sd 
FROM SnapshotDates sd, 
     (SELECT max(x.changeDate) maxChangeDate, x.viewId, x.state 
      FROM SnapshotDates x
     WHERE x.changeDate<:date AND x.viewId in (:viewIds) AND x.state=:state
GROUP BY x.viewId, x.state) sd2
WHERE sd.viewId = sd2.viewId 
      AND sd.state = :state 
      AND sd.changeDate = sd2.maxChangeDate

感谢您的帮助

【问题讨论】：

jpa 不支持“FROM”和“SELECT”子句中的子查询，您必须更改查询并将子查询放在“WHERE”子句中。

标签： hibernate jpa subquery

【解决方案1】：

我不认为 HQL 可以在 from 子句中做子查询

https://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html/ch16.html#queryhql-subqueries

注意句子：

请注意，HQL 子查询只能出现在 select 或 where 子句中。

我想您可以将其更改为本机查询并以这种方式执行。

【讨论】：

【解决方案2】：

你的 SQL 是：

从 SnapshotDates sd 中选择 sd， (SELECT max(x.changeDate) maxChangeDate, x.viewId, x.state FROM SnapshotDates x WHERE x.changeDate<:date and x.viewid in x.state=":state" group by sd2 where sd.viewid="sd2.viewId" sd.state=":state" sd.changedate="sd2.maxChangeDate</p">

你可以像这样重写你的sql

SELECT sd 
FROM SnapshotDates sd, 
WHERE sd.viewId in (:viewIds)
    AND sd.state = :state
    sd.changeDate = (SELECT max(x.changeDate) FROM SnapshotDates x WHERE x.viewId = ds.viewId AND x.state = ds.state)

从示例中寻找灵感

SELECT m FROM Professor m WHERE (SELECT COUNT(e) FROM Professor e WHERE e.manager = m) > 0

http://www.java2s.com/Code/Java/JPA/EJBQLWhereClauseWithSubQuery.htm

我的类似例子我有 SQL

select k.* from kredits k, 
  (select client_id, max(r_date) r_date from kredits k group by client_id) k2 
where k.client_id = k2.client_id 
    AND k.r_date = k2.r_date 
order by k.id

为 PQL 重写它

select k From Kredit k
where k.rDate = (select MAX(k2.rDate) from Kredit k2 where k2.clientId = k.clientId)
order by k.id

会被翻译成

select kredit0_.id as id28_, kredit0_.client_id as client59_28_ from kredits kredit0_ 
where kredit0_.r_date=(select MAX(kredit1_.r_date) from kredits kredit1_ where kredit1_.client_id=kredit0_.client_id) 
order by kredit0_.id

返回与 SQL 相同的结果。

将 Hebirnate 3.3.1 与 MySQL 5.0.24 一起使用

【讨论】：

请帮我翻译查询：select t.order_state,t.claim_number,t.id from (select * from t_repair_order where claim_number='SERCON201465') t where t.order_state = 'Cancel' and not exists ( select 1 from (select * from t_repair_order where claim_number='SERCON201465') tt where tt.id > t.id and tt.order_state <> t.order_state );