1) There seem to be some bugs and limitations in LB (e.g. incorrect cleanup - https://issues.apache.org/jira/browse/HIVE-14886) and nobody appears to as much as watch JIRAs ;) Does anyone actually use this stuff? Should we nuke it in 3.0, and by 3.0 I mean I’ll remove it from master in a few weeks? :)
2) I actually wonder, on top of the same SQL syntax, wouldn’t it be much easier to add logic to partitioning to write skew values into partitions and non-skew values into a new type of default partition? It won’t affect nearly as many low level codepaths in obscure and unobvious ways, instead keeping all the logic in metastore and split generation, and would integrate with Hive features like PPD automatically. Esp. if we are ok with the same limitations - e.g. if you add a new skew value right now, I’m not sure what happens to the rows with that value already sitting in the non-skew directories, but I don’t expect anything reasonable...
