Got it. On Thu, Feb 12, 2015 at 11:44 AM, Julian Hyde <[email protected]> wrote:
> RelMdDistribution (the "Md" that distinguishes it from > "RelDistribution" stands for "metadata") is just theory, but it will > look a lot like RelMdCollation. > > > https://github.com/apache/incubator-calcite/blob/master/core/src/main/java/org/apache/calcite/rel/metadata/RelMdCollation.java > > On Wed, Feb 11, 2015 at 6:47 PM, Ashutosh Chauhan <[email protected]> > wrote: > > I think RelDistribution as a member of Exchange (as in Julian proposal) > > makes more sense as compared to mine at field level. > > > > On Wed, Feb 11, 2015 at 6:42 PM, Jacques Nadeau <[email protected]> > wrote: > > > >> Does RelMdDistribution exist or as theory? > >> > >> Definitely inclined to "Exchange" over "Shuffle" as more > generic/consistent > >> with Volcano. > >> > >> Note, looking at Ashutosh I wonder a little about the need to have range > >> versus hash at the field information level. I'm sure we can come up > with a > >> use case but it seems to overcomplicate. We already have space > exploration > >> problems when trying to do distribution subsumption for joins with trait > >> propagation so I would be cautious about adding more dimensions to that > >> attribute. > >> >
