JPQL：CASE WHEN 中的布尔表达式需要与 TRUE/FALSE 进行显式比较？

Question

我尝试过以下操作：

SELECT NEW com.kawoolutions.bbstats.view.ScheduleGameLine(
    ga.id                                                                      AS gid
  , ga.scheduledTipoff                                                         AS scheduledtipoff
  ...
  , sch.finalScore                                                             AS homefinalscore
  , sca.finalScore                                                             AS awayfinalscore
  , CASE WHEN pah.wasWithdrawn OR paa.wasWithdrawn THEN TRUE ELSE FALSE END    AS waswithdrawn
  )

最后一行很重要。根据

JPQL/HQL 和 JPA/ Hibernate：选择构造函数表达式中的布尔表达式不起作用（意外的 AST 节点：AND、NPE、HqlSqlWalker.setAlias）？

需要 CASE WHEN。然而，当运行这个时，Hibernate 失败了，

Exception in thread "main" java.lang.IllegalArgumentException: org.hibernate.hql.ast.QuerySyntaxException: unexpected AST node: . near line 19, column 18
     at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:54)
     at org.hibernate.hql.ast.QuerySyntaxException.convert(QuerySyntaxException.java:47)
     at org.hibernate.hql.ast.ErrorCounter.throwQueryException(ErrorCounter.java:82)
     at org.hibernate.hql.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:261)
     at org.hibernate.hql.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:185)
     at org.hibernate.hql.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:136)
     at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:101)
     at org.hibernate.engine.query.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
     at org.hibernate.engine.query.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:124)
     at org.hibernate.impl.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:156)
     at org.hibernate.impl.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:135)
     at org.hibernate.impl.SessionImpl.createQuery(SessionImpl.java:1770)
     at org.hibernate.ejb.AbstractEntityManagerImpl.createQuery(AbstractEntityManagerImpl.java:272)

它显然不受 JPA/Hibernate 语法的支持，但作为 Java 和 DB 程序员，我希望这样的表达式能够工作，比如 if ( hasHitHard ) ... 和/或 SELECT was_withdrawn ..为什么

这样做或者为什么没有像我预期的那样得到支持？

Answer 1

我不确定 select 子句是否支持 AS 运算符，但在这种情况下它无论如何都是多余的。至于 CASE 运算符，也许简单的 pah.wasWithdrawn 或 paa.wasWithdrawn 就足够了：

SELECT NEW com.kawoolutions.bbstats.view.ScheduleGameLine(
     ga.id,ga.scheduledTipoff,...,
     sch.finalScore, sca.finalScore,
     pah.wasWithdrawn OR paa.wasWithdrawn
) from ...