The semantics are a bit undefined--the sane extension of the model to support this is that the default value would show up in every window (otherwise which window would the default value belong to), but we don't have support for enumerating windows (or truncating infinite collections in batch mode).
On Thu, Nov 21, 2019 at 4:55 AM Robin Qiu <[email protected]> wrote: > > Hi all, > > When I run a Combine.globally() transform with a default value set, on a > PCollection windowed by a FixedWindow, I got this error message: > > java.lang.IllegalStateException: Default values are not supported in > Combine.globally() if the input PCollection is not windowed by GlobalWindows > ... > (from here) > > Is this unsupported because it is not implemented yet, or is this a design > decision to not support default values with windows other than GlobalWIndow > (e.g. because the semantics is not well defined)? Where can I learn more > about this? > > Best, > Robin
