Hash partitioning

Another way of partitioning the metrics table is to hash partition on the host and metric columns.

In the example above, the metrics table is hash partitioned on the host and metric columns into four buckets. Unlike the range partitioning example earlier, this partitioning strategy will spread writes over all tablets in the table evenly, which helps overall write throughput. Scans over a specific host and metric can take advantage of partition pruning by specifying equality predicates, reducing the number of scanned tablets to one. One issue to be careful of with a pure hash partitioning strategy, is that tablets could grow indefinitely as more and more data is inserted into the table. Eventually tablets will become too big for an individual tablet server to hold.