Chained map-reduce is not available in the open source BigCouch project, only on our hosted service at cloudant.com. Sorry!
B. On 14 December 2011 09:01, Alon Keren <[email protected]> wrote: > I've been working on an open-source tool with a similar approach chaining > map-reduce: > https://github.com/afters/Couch-Incarnate > > The need to pay the bills withheld me from putting more time into it > lately, so I can't say it's production quality. > Hopefully, this will change soon. > > Dominic - the method I currently use in production is to poll the changes > on my DB every few seconds and update a 'summary' DB accordingly. It's not > pretty, but it works. I hope to replace it with Couch-Incarnate asap. > > Alon > > On 14 December 2011 10:50, Dave Cottlehuber <[email protected]> wrote: > >> On 14 December 2011 05:46, Dominic Tarr <[email protected]> wrote: >> > hi, >> > >> > I need a iterative map reduce, prefurably, in couchdb. >> > >> > I want to be able to do a map reduce to generate unique items, then >> another >> > map reduce to generate stats about those unique items. >> > >> > from what I know about couchdb at the moment, it seems like id have to do >> > the first step at the document creation step, which is just ugly. >> >https://mail.google.com/mail/?shva=1#inbox >> > has anyone else dealt with this problem? >> >> Hi Dom, >> >> Cloudant do this in BigCouch which they released as open source a >> while back http://support.cloudant.com/kb/views/chained-mapreduce-views >> there are a few other posts on chained MR around but I don't know of a >> better Couch-style implementation. Their basic approach is to copy the >> view output into a new db which you'd then re-MR as required. Rinse >> and repeat until complete. >> >> Depending on your data it might be possible to implement their >> view->copy to db -> new view approach yourself in native couch. It >> would be interesting to do this as a couch extension using that nifty >> plugin interface that hasn't been developed yet! >> >> A+ >> Dave >>
