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Parent child join query

Raaj Aaryan

Joined: Feb 07, 2008
Posts: 4

I have a parent table and a child table with one-to-many relationship. Each parent record is related to one or more child records.

For example each record in PEOPLE (parent table) has one or more records in PHONE (child tables).

I have an application which generates an XML file from the result object returned from the PEOPLE table. The structure of the output is like

If I run a simple query on the PEOPLE table due to the association with the PHONE table, it runs a series of associated select on the child tables. To avoid this I make use of from the parent table onto the child table. But when I run this query I get duplicated entries for each record which has more than one phone number.

I think I have to make use of tuple queries to remove this duplication in results, but not sure how to do it. Can anyone suggest me the approach to do it.

thanks in advance
Mark Spritzler

Joined: Feb 05, 2001
Posts: 17276

Please post your mapping files, and your code for the query.


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Raaj Aaryan

Joined: Feb 07, 2008
Posts: 4
Here is the mapping file of the parent table

and the query is

I have tried to remove these duplications using a tuple query but I am still curious to solve my earlier problem
I agree. Here's the link:
subject: Parent child join query
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