You could use the client side method drillDownOnNode
and pass the hierarchical index(e.g "0:0:1") of the node that you want to be drilled. The drill down feature is useful in case that you want to observe a particular branch of the hierarchy. For the Q2.2013 we are going to do our best to introduce a DataBinding Provider which will give us the ability to filter the datasource to which the control is bound.
Regarding to your last concern, you are correct if the data base is changed the hierarchical index will be changed too.
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