What I want to achieve: Select a susbset of entities that have a property value that exists in a List of values. This list is returned by another Query.
In plain SQL, this can be easily achieved with subqueries. This is the Criteria query that returns the relevant values:
DetachedCriteria subq = DetachedCriteria.forClass(MyClass.class)
.setProjection(
Projections.projectionList()
.add(Projections.alias(Projections.max("interestingVal"), "interestingVal"))
.add(Projections.groupProperty("someval1"))
.add(Projections.groupProperty("someval2"))
.add(Projections.groupProperty("someval3"))
);
I would then like to select the entities that have a value of interesting_val that was returned by the above query. Like so:
List<MyClass> resultList = sessionFactory.getCurrentSession().createCriteria(MyClass.class)
.add(Subqueries.propertyIn("interestingVal", subq))
.list();
Unfortunately, the subq
subquery returns a List of Object-arrays with length 4, since I have 4 Projection values. All projection values seem to be automatically added to the SELECT clause. This results in an
SQLSyntaxErrorException: ORA-00913: too many values
.
How can I either tell my second Criteria query to only use the first element in the Object array or only retrieve the first column in my subquery?