Hi, I am trying to implement a UDAF of Kurtosis (<�a href="http://en.wikipedia.org/wiki/Kurtosis";>http://en.wikipedia.org/wiki/Kurtosis<�/a> in the hive. I already found a library to do it, from Apache commons math (<�a href="http://commons.apache.org/math/apidocs/org/apache/commons/math/stat/descriptive/moment/Kurtosis.html";>http://commons.apache.org/math/apidocs/org/apache/commons/math/stat/descriptive/moment/Kurtosis.html<�/a>). But it does NOT support merging partial result in it. I am not a Math guru, so I don't know if this Kurtosis can be done in parallel or not. My question is simple, if I use the above library to implement this UDAF in hive, is there a configuration in the hive (either at runtime or at UDAF level) to make surethat for this UDAF I implemented, the terminatePartial/merge will NEVER be invoked? I have 2 settings I think maybe will do the trick: 1) set hive.exec.reducers.max=12) set hive.map.aggr=false Does either one will do the thing I want? Or anything else? Or is it even possible? Thanks Yong
