Should we give the option to avoid writing to the disk when writing a Datafile to the cloud?

[cortadocodes]

I have a use case where I just want to write data to the cloud and don't want to open it again locally. It is probably much more efficient to only write to the cloud without writing to disk as well, but I can't do this with the Datafile class, which writes to disk and the cloud so further operations on the data are quick as they don't rely on downloading from the cloud again. I could write only to the cloud with the cloud storage client of course, but it would be nice to be able to use Datafile to do this. Is this a writing mode we should allow @thclark?

[thclark]

The answer is almost certainly yes; but chuck it onto the backlog for now because we don’t want to prioritise until we have a clear performance cost to this.