World-Class Data Compression
When you are creating PowerPivot data sets, all of the data is loaded into computer memory. When you save a PowerPivot workbook, the data from the imported text files is stored in the workbook. Amir Netz from the PowerPivot team came up with an impressive methodology for compressing the data.
Figure 2.28 tells an impressive story. This chapter mashed up a text file that occupies 58MB. It also incorporated the StoreInfo.xlsx file which takes up 19K. All of that data is stored in the StoreMashup.xlsx file in an amazingly small 3.6MB file (see Figure 2.29).
Figure 2.29 58MB of text file fits in a 3.6MB Excel file.