For you hard core techies out there, stop reading now. This post is for those people in the world who had no idea that the Office 2007 (and upwards) files are actually just a bunch of files zipped up. I was curious to see how PowerPivot Data was stored with the Excel spreadsheet and was amazed to find out that a number of my associates were unaware of the make up of the new Excel formats.
In order to illustrate the concept take an Excel (or Word) 2007/2010 file and just to be safe make a copy of it. Then change the file extension from XLSX to ZIP and then open in Winzip. Shock and horror we find a whole bunch of files (mostly XML) in various directory structures. This was done in order to comply with Office Open XML Format. Read all about it here.
Back to the original question about how the PowerPivot Data is stored. It is stored in a directory called xl\customData with the extension DATA within the Excel (zip) file. Here is a bit more on how the data interacts with your memory.
- Paul Steynberg