Java hibernate uses addentity to create sqlsql

I need to apply SQL queries similar to this

SELECT
    id as id,c03 as c03,c34 as c34 
FROM
    (SELECT
        id,c03,c34 
    FROM
        students
    where
        c34 in(
            ?,?,?
        ) 
    order by
        id desc) o 
group by
    c34;

And my java code

private final void retrieveStudents(){
    final List result = currentSession()
            .createsqlQuery("SELECT id as id,c34 as c34 FROM (SELECT id,c34,c03 FROM students where c34 in(:filters) order by id desc) o group by c34;")
            .setParameterList("filters",Arrays.asList(74,1812))
            .list();
    result.forEach(this::consumer1);
}

This query is OK Returns an array of objects that can be iterated, but I want to return a student object, so I add

.addEntity(Student.class)

But I was wrong

Column 'ACTIVE' not found.

I'll try it, too Addscalar, but the same thing happens

.addScalar("id",org.hibernate.type.IntegerType.INSTANCE)
.addScalar("c03",org.hibernate.type.DateType.INSTANCE)

Which is the student's column, but it's not my problem. What should I do? I just think that the alias hibernate should be used to fill the student entity in some way

All I want is a student object filled with ID and C34 values

What is possible that I did wrong?

Solution

For this use case, you don't want hibernate to treat student as an entity, but as a dto

To do this, do not use the addentity method, but setresulttransfomer:

final List result = currentSession()
        .createsqlQuery("SELECT id as id,c34 as c34 " + 
                         "FROM (SELECT id,c03 FROM students " + 
                               "where c34 in(:filters) " + 
                               "order by id desc) o group by c34")
        .setParameterList("filters",1812))
        .addScalar("id",org.hibernate.type.IntegerType.INSTANCE)
        .addScalar("c03",org.hibernate.type.DateType.INSTANCE)
        .addScalar("c34",org.hibernate.type.DateType.INSTANCE)
        .setResultTransformer(Transformers.aliasToBean(Student.class))
        .list();

This is valid for non entity classes as long as the class has a setter that matches the name of the projection column and has a parameterless constructor I've never tested this on an entity class

If you do not have a setter but a constructor for these three fields, you can use:

// choose here the right constructor
java.lang.reflect.Constructor constructor = Student.class.getConstructors()...
// ...
.setResultTransformer(new AliasToBeanConstructorResultTransformer(constructor));

Replace

Edit: I won't use an entity as a dto (but create a specific dto for this use case): if one of your services thinks that the entity is loaded in a normal way (so it is fully initialized), make some modifications (update a field as an example), and save the entity?

In the best case, non nullable fields (on the DB side) will not be initialized. You will receive a constraintviolationexception and trigger a rollback to keep the data safe

In the worst case, you will destroy the data by setting all fields of the entity to null and three loaded fields to null