Retrieve one parent and one child only in one HQL ?

Yashnoo · **Joined:** Wed Dec 17, 2003 4:24 am **Posts:** 188

Hi friends

I want to know if it is possible retrieve one parent and only one child in on HQL.
I mean that I want to get a child and a parent in one sql .

I try this:

Code:

select p.parentName,c.childName,elements(p.childSet).get(0) from Parent p,Child c

But it can't parse compile. Hibernate's HQL is object SQL, So I think it maybe work in this way,right?

If someone know how to do it ,please tell me , Thks!

Yashnoo · **Joined:** Wed Dec 17, 2003 4:24 am **Posts:** 188

It is Possible? Or anyone has another solution?

madhusudanmk · **Joined:** Mon Dec 13, 2004 2:32 am **Posts:** 8

Sound like a one-2-oen relationship why not try one-2-one relationship feature of hibernate.

Check out the hibernate manulate for feature capabilities.

joshua · **Posted:** Fri Dec 31, 2004 9:39 am

Yashnoo wrote:

Hi friends

I want to know if it is possible retrieve one parent and only one child in on HQL.
I mean that I want to get a child and a parent in one sql .

I try this:

Code:

select p.parentName,c.childName,elements(p.childSet).get(0) from Parent p,Child c

But it can't parse compile. Hibernate's HQL is object SQL, So I think it maybe work in this way,right?

If someone know how to do it ,please tell me , Thks!

That seems like the hard way to do it. If you have a backpointer from Child to Parent e.g. a many-to-one from child to parent, and that is mapped to the 'parent' property of child, you can do this:

Code:

select c.childName, c.parent.parentName from Child c

or even:

Code:

from Child c

and then use Java code in your application to access the properties, e.g.

Code:

Child c = ... get result from the above query ...
String x = c.getParent().getParentName();
String y = c.getChildName();

Yashnoo · **Joined:** Wed Dec 17, 2003 4:24 am **Posts:** 188

Thank you . I WILL try it ！