A qvw file is essentially the file that describes your application, including the load script, the variables, all chart objects with their dimensions / expressions / settings. Not forgetting defined Macros.
By default, a qvw file also stores the data model and the contained data after a perfomed data load, but you can remove this from the qvw file when saving.
I believe the data part of the qvw is a compressed storage of the internal data model, and I believe it is not a cube.
For more information about the data model and internal data storage, please check the whitepapers available from the Qliktech Web site and from the document section here in the forum. Also these blogs might be useful:
The data model in a qvw file is relational and it is exactly what you see when you look at the table structure (ctrl-t).
In addition, every chart is a virtual cube. "Cube" in the sense that it is a matrix of numbers in exactly the same way as OLAP tools have cubes. But nothing is pre-calculated: no data is stored in it, so it is "virtual". It is defined through the formulae for its dimensions and measures and is completely calculated every time the user clicks, using the data in the relational model.
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