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Problem with querying and one to many relationship..

Annie Jones

Joined: Nov 05, 2007
Posts: 10

I have the following mappings in my hibernate hbm.xml file (this cannot be changed, the table structure has been decided by the DBA):

We are passing these Postcode objects through to struts instead of having data transfer objects, this is read only data - the application will never modify any postcode/suburb information.

My problem is that I need a query that gives the same result as the following two queries:

but instead of returning Suburb objects and Postcode objects, only returns Postcode objects. As you can see, the first query will return Suburb objects as I am searching on the nzTownCity or nzSuburb columns because the suburbRequiredFlag is set to 'Y' on the Postcode.

I know this seems fairly complicated but if there is a way that I can get only Postcode objects with the matching Suburb objects (instead of all the Suburb objects that are bound to a Postcode because of the one-to-many relationship) then that would be great.

Thanks in advance,

Abraham Gimeno

Joined: Jul 16, 2008
Posts: 7
I don't know if I understood well but, have you tried

and since it's ManyToOne you should be able to access Postcode object

It is sorta covered in the JavaRanch Style Guide.
subject: Problem with querying and one to many relationship..
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