We have discussed before whether ordering and partitioning should be distinct traits or the same trait. I was (still am) ambivalent about it. I’ve been having some discussions with the Hive team, and it looks as if they will make ordering & partitioning the same trait.
Julian On Jan 19, 2015, at 9:51 AM, Jinfeng Ni <[email protected]> wrote: > For the case of "partition by x sort by y", I think planner currently keeps > the partition / sort in separate trait; "partition by x" as a distribution > trait, "sort by y" as a collation. Distribution trait has higher priority > than the sort collation. Drill's physical operators will have both those > traits, when doing planning work. > > > On Sun, Jan 18, 2015 at 9:33 PM, Jacques Nadeau <[email protected]> wrote: > >> In planning we currently state collation as total ordering. In some cases >> it would be useful to create a concept of local ordering. For example, >> partition by x then sort by y. Does anyone have any thoughts on how we >> should define this in terms of traits/physical properties? The syntax would >> realistically only apply to ctas or as a description of existing files so I >> think we shouldn't need to enhance the language beyond those locations. >> >> J >>
