Performing MapReduce operations
MapReduce is the programming model to perform operations (mainly aggregation) on distributed sets of data across various clusters in different servers. This concept was coined by Google and was used in the Google file system initially and later was adopted by the open source Hadoop project.
MapReduce works by processing the data on each server and then combine it together to form a result set. It actually divides into two operations namely Map and Reduce.
- Map: This performs the transformation of the elements in the group or individual sequence
- Reduce: This performs the aggregation and combines the results from Map into a meaningful result set
In RethinkDB, MapReduce queries operate in three steps as follows:
- Group operation ...
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