Syntax error, QueryDSL "Case when" on map <>, with aggregation

Question

I have a table eventand a table eventDatarelated to both Map<>Hibernate

event → Map <> eventDatas

@OneToMany(fetch=FetchType.LAZY)
@JoinColumn(name = "event_id", referencedColumnName = "event_id")
@MapKey(name = "idk.key")
public Map<DATA_KEY, eventData> getEventDatas() {
    return eventDatas;
}

Then I have this QueryDSL to retrieve populations eventgrouped by date.

If it Map<>contains a pair DATA_KEY.CODE=202, the group "OK"otherwise, if this pair is absent or has a different meaning, the group "FAIL".

final QEvent event = QEvent.event;

Expression<String> groupCase = 
    event.eventDatas.get(DATA_KEY.CODE).valueInt 
    .when(202).then("OK") 
    .otherwise("FAIL");

ConstructorExpression<StatDto> constructor = 
    Projections.constructor(StatDto.class, event.date, event.count(), groupCase);

query.select(constructor) 
    .from(event) 
    .leftJoin(event.eventDatas) 
    .groupBy(event.date, groupCase) 
    .orderBy(event.date.asc());

return query.fetch();

This request returns an error:

org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: with near line 2, column 73 
[select event.date, count(event), case when event_eventDatas_0.valeurInt = ?1 then 'OK' else 'FAIL' end
from event.eventDatas as event_eventDatas_0 with key(event_eventDatas_0) = ?2, entitystat.event event
  left join event.eventDatas
group by event.date, case when event.eventDatas.get(?2).valeurInt = ?1 then 'OK' else 'FAIL' end
order by event.date]
    at org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:91)
    at org.hibernate.hql.internal.ast.ErrorCounter.throwQueryException(ErrorCounter.java:109)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:304)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:203)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:158)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:131)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:93)
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:167)
    at org.hibernate.internal.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:301)
    at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:236)
    at org.hibernate.internal.SessionImpl.createQuery(SessionImpl.java:1836)
    at com.querydsl.jpa.hibernate.DefaultSessionHolder.createQuery(DefaultSessionHolder.java:36)
    at com.querydsl.jpa.hibernate.AbstractHibernateQuery.createQuery(AbstractHibernateQuery.java:104)
    at com.querydsl.jpa.hibernate.AbstractHibernateQuery.createQuery(AbstractHibernateQuery.java:97)
    at com.querydsl.jpa.hibernate.AbstractHibernateQuery.fetch(AbstractHibernateQuery.java:174)

Without groupCasethe request, the error will disappear, indicating that the problem comes from the case itself.

What is the correct syntax for using case Map<>aggregation?

Addendum:

with from:

from event.eventDatas as event_eventDatas_0 with key(event_eventDatas_0) = ?2

SQL, Hibernate groupCase:

select event0_.date as col_0_0_, count(event0_.event_id) as col_1_0_ 
from event event0_ 
group by event0_.date
order by event0_.date

Answer 1

, sql.

event.date,
(),
, event_eventDatas_0.valeurInt =? 1, "OK" "FAIL" end

event.eventDatas event_eventDatas_0 (event_eventDatas_0) =? 2, entitystat.event event left join event.eventDatas
group by event.date, case when event.eventDatas.get(?2).valeurInt = ?1 then 'OK' else 'FAIL' end
event.date

, Projection refference

sql group by event.date, alisaName

SQL- :

event.date,
(),
case, event_eventDatas_0.valeurInt =? 1, 'OK' else 'FAIL' end as aliasName

event.eventDatas event_eventDatas_0 (event_eventDatas_0) =? 2, entitystat.event event left join event.eventDatas
group by event.date, aliasName
event.date

, , ( Alias ​​- ).

final QEvent event = QEvent.event;
final QEventData eventData = QEventData.eventData;

String alias="alias";

Expression<String> groupCase = 
event.eventDatas.get(DATA_KEY.CODE).valueInt 
.when(202).then("OK") 
.otherwise("FAIL").as(alias);

ConstructorExpression<StatDto> constructor = 
Projections.constructor(StatDto.class, event.date, event.count(), groupCase);

query.select(constructor) 
.from(event) 
.leftJoin(event.eventDatas,eventData) 
.groupBy(event.date, alias) 
.orderBy(event.date.asc());

return query.fetch();

Answer 2

, , :

• -, , .

, Hibernate, , , CASE WHEN .

, , EventData, CASE WHEN StatDto, :

@QueryProjection:

class StatDto {

  private Date eventDate;
  private int eventCount;
  private String eventDataStatus;

  @QueryProjection
  public StatDto(Date eventDate, int eventCount, int eventDataKey){
     this.eventDate = eventDate;
     this.eventCount = eventCount;
     if (eventDataKey == 202) {
        this.eventDataStatus = "OK";
     } else {
        this.eventDataStatus = "FAIL";
     }
  }

}

:

query.from(event) 
    .leftJoin(event.eventDatas) 
    .groupBy(event.date, groupCase) 
    .orderBy(event.date.asc())
    .list(ConstructorExpression.create(StatDto.class, event.date, event.count(), event.eventDatas.get(DATA_KEY.CODE).valueInt));

. , , - , .

, !