Ahh, perfect. The docs don't agree terribly well but the case study is great. The context for when merge() gets called was not clear to me.
Thanks guys! Pat -----Original Message----- From: Steven Wong [mailto:sw...@netflix.com] Sent: Thursday, March 10, 2011 6:24 PM To: user@hive.apache.org Cc: Christopher, Pat Subject: RE: UDAF documentation Take a look at http://wiki.apache.org/hadoop/Hive/GenericUDAFCaseStudy, in case you haven't found it already. -----Original Message----- From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Thursday, March 10, 2011 6:18 PM To: user@hive.apache.org Cc: Christopher, Pat Subject: Re: UDAF documentation On Thu, Mar 10, 2011 at 8:27 PM, Christopher, Pat <patrick.christop...@hp.com> wrote: > Hi Guys, > > I'm writing a UDAF to run against hive 0.5 or hive 0.7. The documentation I > can find says to implement UDAFEvaluator and ensure that you implement > init() , aggregate() and evaluate(). However, all of the examples I can > find implement init(), iterate(), merge(), terminatePartial() and > terminate(). > > > > What's the difference and where I can find the documentation on how to write > a UDAF? > > > > Thanks, > > Pat At time the documentation may lag behind the code. I would checkout the hive source code for the version you are working with and base your work on other already existing UDAF's that are similar. Edward
