Query based on a collection's contents?

biot023 · **Posted:** Sat Oct 08, 2005 11:53 am

Hallo -- my question is based upon the following example classes:
First, the class MyClass:

Code:

public class MyClass{
    private Long id;
    private Set<MyOtherClass> myOtherClasses;
    public Long getId(){return id;}
    protected Long setId(Long id){this.id=id;}
    public Set<MyOtherClass> getMyOtherClasses(){
        return myOtherClasses;
    }
    public void setMyOtherClasses(Set<MyOtherClass> myOtherClasses){
        this.myOtherClasses=myOtherClasses;
    }
}

And also the class in the collection, MyOtherClass:

Code:

public class MyOtherClass{
    private Long id;
    private String value;
    public Long getId(){return id;}
    protected Long setId(Long id){this.id=id;}
    public String getValue(){return value;}
    public void setValue(String value){this.value=value;}
}

Having established that, my question is -- would it be possible to construct an HQL query that returned instances of MyClass whose collections myOtherClasses contained one or more instances of MyOtherClass whose value attribute was equal to "Hello."?
In (bad) pseudo-code, this might be:

Code:

SELECT from MyClass c WHERE c.myOtherClasses CONTAINS MyOtherClass.value=="Hello."

Sorry -- I know that's a terrible attempt to express it -- that's why I ask for help!
Cheers,
doug.

bruno.borges · **Posted:** Sat Oct 08, 2005 2:26 pm

Well, first of all you could read the HQL sintax documentation.

Secondlly, ... you could read the very well documented HQL sintax ... :)

http://www.hibernate.org/hib_docs/v3/re ... ryhql.html

biot023 · **Posted:** Sun Oct 09, 2005 6:59 am

Fair enough, I was just hoping that someone already knew & could give me some pointers, time & deadlines being what they are.

drooler · **Joined:** Tue Jun 29, 2004 12:35 pm **Posts:** 21

biot023 wrote:

Fair enough, I was just hoping that someone already knew & could give me some pointers, time & deadlines being what they are.

This might work (tangled w/same problem myself some time ago):

Select aMyClass from MyClass as aMyClass inner join aMyClass.MyOtherClasses as aMyOtherClasses where aMyOtherClasses.value='hello'

biot023 · **Posted:** Sun Oct 09, 2005 3:16 pm

Cheers for that, man -- that looks bang on!
doug.