Hi, For buckets with a significant number of records, it makes a lot of sense to run the example I provided with 'do_prereduce' enabled as it will result in considerably less data being sent between the nodes. This can be enabled as follows:
curl -XPOST http://localhost:8098/mapred -H 'Content-Type: application/json' -d '{"inputs":{ "bucket":"goog", "index":"$bucket", "key":"goog" }, "query":[{"reduce":{"language":"erlang", "module":"riak_kv_mapreduce", "function":"reduce_count_inputs", "arg":{"do_prereduce":true}}}]}' Best regards, Christian On 14 Feb 2013, at 08:01, Christian Dahlqvist <christ...@basho.com> wrote: > Hi Jeremiah, > > It does indeed not seem to be documented on the main docs site, and I will > try to correct this. The only place I have found it described is on the wiki > for the Ruby client > (https://github.com/basho/riak-ruby-client/wiki/Secondary-Indexes). > > Below is also an example of a simple mapreduce job that shows how to count > the number of records in the 'goog' bucket based on the $bucket secondary > index: > > curl -XPOST http://localhost:8098/mapred > -H 'Content-Type: application/json' > -d '{"inputs":{ > "bucket":"goof", > "index":"$bucket", > "key":"goof" > }, > "query":[{"reduce":{"language":"erlang", > "module":"riak_kv_mapreduce", > "function":"reduce_count_inputs"}}]}' > > I hope this helps. > > Best regards, > > Christian > > > On 13 Feb 2013, at 18:12, Jeremiah Peschka <jeremiah.pesc...@gmail.com> wrote: > >> Is this documented anywhere on the docs.basho.com site? >> >> Searching for $bucket produces search results just for "bucket" and Google >> says "No results found for site:docs.basho.com $bucket." >> >> --- >> Jeremiah Peschka - Founder, Brent Ozar Unlimited >> MCITP: SQL Server 2008, MVP >> Cloudera Certified Developer for Apache Hadoop >> >> >> On Wed, Feb 13, 2013 at 10:08 AM, Christian Dahlqvist <christ...@basho.com> >> wrote: >> Hi, >> >> In addition to the $key index, there is also a $bucket index available by >> default. This contains the name of the bucket, and can be used to get all >> keys in a specific bucket. >> >> Best regards, >> >> Christian >> >
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