We have introduced our RadPivotGrid and its OLAP support in our latest official release. However, we could not provide estimate for the OLAP drill through support. Note that we will introduce a demo showing how drill through could be achieved with custom code using SqlDataSource. If you could make manual requests to the OLAP you will be able achieve the desired functionality by replacing the requests to the SqlDataSource. The demo will be available for the next Service Pack release.
the Telerik team
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