mapreduce

I have a background working with relational databases but recently started to dabble in CouchDB and was surprised by how some non-relational…

My mapper emits 'uniq key' - 'very large value' pair. My reducer doesn't know the key is unique. Thus, reducer waits all the mappers are completed.…

Our organization has hundreds of batch jobs that run overnight. Many of these jobs require 2, 3, 4 hours to complete; some even require up to 7…

I have been using CouchDB for quite sometime without any issues. That is up until now. I recently saw something in my map/reduce results which I had…

How could i combine with map/reduce these two files: File1. Data. 1 name:foo1,position:bar1 2 name:foo2,position:bar2 3 name:foo3,position:bar3 4…

I've recently started working with Hadoop and have been learning how to write MapReduce jobs. All over the internet, I can find examples and…

I have a use case where I want to process data and generate output of fixed size , say 1 GB i.e. each map-reduce job output should be 1 Gb. Does…

I just learned about the collect_set() function in Hive, and I started a job on a development 3-node cluster. I only have about 10 GB to process.…

Let's say I have a dataset like the following: { "_id" : ObjectId("4dd51c0a3f42cc01ab0e6506"), "views" : 1000, "status" : 1 } { "_id" :…

What I want: I have a master collection of products, I then want to filter them and put them in a separate collection.…

what seemed a simple task, came to be a challenge for me. I have the following mongodb structure: { (...) "services": { "TCP80": { "data": [{…

I am currently using MongoDB's MapReduce to generate hourly ad view counts like this: { _id : "4/1/2011 9:00 AM", value : { AdViews_Total : 4 } }…

I have two documents that looks a bit like so: Doc { _id: AAA, creator_id: ..., data: ... } DataKey { _id: ..., credits_left: 500, times_used: 0,…

I am studying to use mahout, and get the following message after running one of its example: Exception in thread "main"…

I want to know how to delete specific rows in HBase using Map-Reduce?

After reading this and this paper, I decided I want to implement a distributed volume rendering setup for large datasets on MapReduce as my…

I'm having trouble wrapping my head around how map/reduce works in MongoDB. I have a collection with the fields: areacode, state, county, zip, city,…

I have a question about configuring Map/Side inner join for multiple mappers in Hadoop. Suppose I have two very large data sets A and B, I use the…

After runing a MapRed job, we will get some summary about the job, for example: ... reduce input records: 10 reduce input groups: 3 ... I knows this…

I am a Technical Recruiter in the Greater Puget Sound area and feel this would me a great place to post my clients needs.