What can we say about partitioning with key and round robin?
The partitioning with key (also called hash partition) is partitioning method used when we have diverse keys. The technique is used basically in the processing of parallel data. On the other hand round robin partitioning is a technique that allows us to distribute the data on every destination partition uniformly. While in the case of partitioning with key we can have large data skew due to large key volume, in the case of using round robin partitioning the skew is zero.