Uploaded image for project: 'Apache Arrow'
  1. Apache Arrow
  2. ARROW-12650

[Doc][Python] Improve documentation regarding dealing with memory mapped files

    XMLWordPrintableJSON

Details

    Description

      While one of the Arrow promises is that it makes easy to read/write data bigger than memory, it's not immediately obvious from the pyarrow documentation how to deal with memory mapped files.

      The doc hints that you can open files as memory mapped ( https://arrow.apache.org/docs/python/memory.html?highlight=memory_map#on-disk-and-memory-mapped-files ) but then it doesn't explain how to read/write Arrow Arrays or Tables from there.

      While most high level functions to read/write formats (pqt, feather, ...) have an easy to guess memory_map=True option, the doc doesn't seem to have any example of how that is meant to work for Arrow format itself. For example how you can do that using RecordBatchFile*

      An addition to the memory mapping section that makes a more meaningful example that reads/writes actual arrow data (instead of plain bytes) would probably be helpful

      Attachments

        Issue Links

          Activity

            People

              amol- Alessandro Molina
              amol- Alessandro Molina
              Votes:
              0 Vote for this issue
              Watchers:
              4 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved:

                Time Tracking

                  Estimated:
                  Original Estimate - Not Specified
                  Not Specified
                  Remaining:
                  Remaining Estimate - 0h
                  0h
                  Logged:
                  Time Spent - 6h 50m
                  6h 50m