Tag: compression
All the articles with the tag "compression".
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Windows Already Ships the Decompressor Power Pivot Needs
VertiPaq's xpress8 compression is raw MS-XCA LZ77 behind a two-field wrapper, and Windows has shipped a decoder for it all along. Enough to read the Power Pivot model inside an Excel workbook from a PowerShell script with no dependencies.
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How VertiPaq Sorts a Table — A Visual Walkthrough
A visual companion to the row-ordering article — step through the greedy bucket-splitting algorithm that VertiPaq uses to maximise RLE compression.
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How VertiPaq Sorts Rows to Maximize RLE Compression
How VertiPaq appears to use a greedy row-reordering algorithm to maximise RLE compression across all columns in a segment.
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Reconstructing Column Data from .idf and .idfmeta
How VertiPaq stores column segments in .idf and .idfmeta files, and how those files combine to reconstruct imported table data from a PBIX file.