Sorting CouchDB Views By Value

Question

I\'m testing out CouchDB to see how it could handle logging some search results. What I\'d like to do is produce a view where I can produce the top queries from the results

Answer 1

The Link Retrieve_the_top_N_tags seems to be broken, but I found another solution here.

Quoting the dev who wrote that solution:

rather than returning the results keyed by the tag in the map step, I would emit every occurrence of every tag instead. Then in the reduce step, I would calculate the aggregation values grouped by tag using a hash, transform it into an array, sort it, and choose the top 3.

As stated in the comments, the only problem would be in case of a long tail:

Problem is that you have to be careful with the number of tags you obtain; if the result is bigger than 500 bytes, you'll have couchdb complaining about it, since "reduce has to effectively reduce". 3 or 6 or even 20 tags shouldn't be a problem, though.

It worked perfectly for me, check the link to see the code !