Does Mongoid have Map/Reduce?
I am using Ruby code to calculate sum from the array returned by M开发者_Go百科ongoid.
But maybe using Map/Reduce can be faster, except I don't see any docs for Map Reduce on mongoid.org and Google for
map reduce site:mongoid.org
doesn't give any result either. (or using MapReduce
or Map/Reduce
)
There are docs on MongoDB's site
map reduce site:mongodb.org
but need to use Map Reduce with Mongoid as well.
You can use map reduce with Mongoid just as you could through the Ruby driver directly:
# Post is a Mongoid model...
Post.collection.map_reduce(map_function, reduce_function, options)
For some examples of doing map reduce in the Ruby driver, see this blog post by Kyle Banker (maintainer of the Ruby MongoDB driver).
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