Question

I have the following relation of three classes:

   @Entity
    public class User{

       @OnetoMany
       List<Attribute> attributes = new ArrayList<Attribute>();
    }

    @Entity
    public class Attribute{
       @ManyToOne
       AttributeType attributeType;

    }

    @Entity
    public class AttributeType{

       @Column
       String type;
    }

One user can have n attributes of m types.

I need to create HQL query which will return all Atribute Types List<AttributeType> of specific user attributes.

For example user has attribute a of type t, atribute b of type t and attribute c of type t1.
I need to return List<AttributeType> which will contain t and t1.

Please help. I just got lost in this query.

Answer 1

You shall map Attribute to User many to one relation, so the following query is what you need:

select distinct atr.attributeType
  from Attribute atr
 where atr.user = :user

I think the following query will work too:

select distinct atrs.attributeType
  from User as user
  join user.attributes as atrs   
 where user.id = :user_id