Named query for entity that does not associate with a specific table

I'm using Quarkus and Hibernate / Panache.

For this example, I have 3 tables (table_a, table_b, table_c) that I am joining together using a native query. In the project I'm working on, it's around 5 JOIN tables to retrieve the information I'm looking for.

table_b is purely a mapping / join table for table_a and table_c:

SELECT 
  a.id,
  a.name, 
  c.login_date 
FROM 
  table_a a 
  JOIN table_b b ON b.a_id = a.id 
  JOIN table_c c ON b.c_id = c.id 
WHERE 
  c.login_date > '01-MAY-21'

I'm porting the above to HQL. I've mapped all my @Entity classes with their respective @Table, along with their @Column names. We're good in that department.

SELECT 
  a.id,
  a.name, 
  c.loginDate 
FROM 
  TableA a 
  JOIN TableA b ON b.aId = a.id 
  JOIN TableB c ON b.cId = c.id 
WHERE 
  c.loginDate > '01-MAY-21'

I'm only looking for name and login_date. There is a bunch of other information stored in table_a and table_c that I don't want for this specific query. So I created an entity for this call:

@Entity
@IdClass(LoginDetailsPk.class)
@NamedQuery(
    name = "LoginDetails.findFromDate",
    query = "FROM TableA a " +
            "JOIN TableA b ON b.aId = a.id " +
            "JOIN TableB c ON b.cId = c.id " +
            "WHERE c.loginDate > '01-MAY-21'"
)
public class LoginDetails extends PanacheEntityBase {

    @Id
    private int id;

    @Id
    private String name;

    @Id
    private String loginDate;

    public static List<LoginDetails> findFromDate(String fromDate) {
        // Eventually pass fromDate into find()
        return find("#LoginDetails.findFromDate").list();
    }

}

I'm having a hard time trying to understand why the return even works. When I invoke LoginDetails.findFromDate(...) and store it in a List<LoginDetails>, it works fine. However, when I try to access the list, I get a ClassCastException error.

List<LoginDetails> details = LoginDetails.findFromDate(null);

for(LoginDetails detail : details) { // <------ Throws a class cast exception
   //...
}

After debugging, I'm noticing that generic type stored in my List isn't even my LoginDetails class; rather, it's an array of objects (List<Object[]>) with all my @Entities and the irrelevant information I'm not looking for.

I'm lost. Would it make more sense to move back to a native query?

from Recent Questions - Stack Overflow https://ift.tt/2TmwCcL
https://ift.tt/eA8V8J