Hi all,
I've got a Hibernate entity, called Event, which has a one-to-many metadata entity, EventData.
Given the following Event:
EventId: 1
EventHash: broccoli
With the following EventDatas:
EventDataId: 1
EventId:1
Field: tag
Value: tagme
EventDataId: 2
EventId: 1
Field: tag
Value: anotherTag
How do I create a Criteria query to retrieve the event which has BOTH tags "anotherTag" and "tagme"? In SQL, I'd join the event_data table once for each tag being searched for, but I can only seem to create one alias for the Event.EventData relationship, i.e.
Code:
int inc = 0;
Conjunction junc = Restrictions.conjunction();
for ( String tag : tags ) {
crit.createAlias("e.EventData", "ed"+inc);
junc.add(
Restrictions.and(
Restrictions.eq("ed"+inc+".field", "tag"),
Restrictions.eq("ed"+inc+".content", tag)
)
);
inc++;
}
Doesn't work; "duplicate association path: Event.EventData"
Similarly, a normal Conjunction doesn't work, because the clause ends up as:
Code:
((ed3_.field='tag' and ed3_.content='anotherTag') and (ed3_.field='tag' and ed3_.content='tagme'))
and, obviously, a database field can't have two different values at the same time.
Any ideas as to how I could clean this up, or is the only option reverting to HQL?