apache spark - Generate multiple key-value pair using transformation step of MapReduce -


in mapreduce framework, map method (transformation) works on each datapoint (k,v) produce new datapoint (k',v'). there mechanism generate pair of datapoints (k',v') , (k'',v'')?

i using apache spark. code snippet here:

javardd<string> myrdd = sc.textfile(...);  javardd<string> newrdd = myrdd.map(                     new function<string, string>() {                          public vector call(string s) {                             ...                         }                     }                     );

by default, size of myrdd , newrdd same. objective have 2 entries in newrdd each datapoint of myrdd. how possible?


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