On Thu, Sep 19, 2013 at 4:44 PM, Julien Le Dem <notifications@github.com>wrote:

> In Encodings.md:
>
> > \ No newline at end of file
> > +encoded back to back.
> > +
> > +### Delta Strings:
> > +
> > +Supported Types: BYTE_ARRAY
>
> We should clarify that we restrict it to sorted input right here.
> Based on the description it sounds like the encoding would be valid even
> on unsorted input (the overhead wouldn't even be that significant as the 0
> prefix length would be RLE'd) and could save space if there's some prefix
> similarity in the data. (Just a thought)
>

I'm not sure how we could (or should) enforce the restriction. And as you
said, this would also work on unsorted data, just not nearly as well.

We could also regard this as a superset of RLE_LENGTH_STRINGS and simply
subsume it (unless we think there's a downside, such as higher decode cost).

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