Reporting Services - HOWTO: Create a DataSet from another DataSet!? Is it possible?

I have a report with two Datasets. The first loads a lot of data displayed in a tablix. The second DataSet is used to display a Chart with an alternative perspective on the same data.

I dont want to load the data twice, so currently I store the data from the first query in a special cache tabl开发者_如何学Goe in the database. The second query reads only from the cache table.

Now it would be much nicer if I could create the second Dataset directly within SSRS and saving this second round-trip to the DB. Preferably I'd like to define the second dataset something like:

SELECT val1, val2 FROM dataSet1 WHERE val3 = 'something'

Anybody know if this is possible?

Any hints appreciated!

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If both the tablix and graph are representing the same data (even from different perspectives), then I would suggest using the same dataset for both the tablix and the graph.