Okay first off; I know JOIN + LATERAL VIEW together isn't working so I moved my JOIN into a subquery and that makes the query work properly
However when I added a MAPJOIN hint for the JOIN in the subquery it will also stop doing the reducer for the main query! This only happens when there's a LATERAL VIEW in there though, if I remove the LATERAL VIEW then the main query still get's a reducer to do grouping Here's a gist: https://gist.github.com/2499436 Containing the queries and a PHP script which you can run to execute the test case I'm using, which does; * setup a database called hive_mapjoin * setup tables * load some test data * do the selects You'll need the https://github.com/rcongiu/Hive-JSON-Serde/downloads json-serde-1.1-jar-with-dependencies.jar with it though and change the path I guess looking at the queries you guys can probally figure out a better testcase, but maybe it's helpful Not sure if this is a bug or me doing something that just isn't supposed to be working, but I can't seem to find any pointers that this wouldn't be supported... Here's another gist with the plan.xml: https://gist.github.com/2499658 I've also created a ticket in JIRA but it doesn't seem to get any attention at all: https://issues.apache.org/jira/browse/HIVE-2992 Greetz, Ruben de Vries
