IIUC, the bit-width could be 0 when the dictionary contains a single entry and then all entry ids are zeros. I haven't tried to create such a file and I suspect that RLE (rather than bit-packing) is in use in this case.
Best, Gang On Thu, Dec 19, 2024 at 9:43 AM Marko Divjak <mdivja...@gmail.com> wrote: > Hi, > > I was exploring the apache arrow code and saw this this > < > https://github.com/apache/arrow/blob/b655852b260d3b8c3fe457795df0f42a2ff9c98c/cpp/src/arrow/util/bpacking64_default.h#L35C1-L40C2 > > > in > the repo. > What does it mean when bit width is zero in dictionary encoded files? > What is the scenario where data will be encoded with bit width zero and how > could such a file be generated? > > Regards, > Marko >
