Hi archana,
Several things could go wrong in a case like this. It could be a problem with the data source setup, with the data you have in the database, or something else, and it is hard for us to say since we can't reproduce the issue. A first step, I'd recommend you check the orbeon.log and look for exceptions there. For instance, if there is an problem with the datasource setup, it will be showing up there. And I'm sorry not to be able to point you to something more precise.
Alex
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