So in this example, would the row look like this?

Row Key                                                                                  Value
---------------------------------------------------------------------------------------
primary\0some-var-len-region-name\0min_region_key           3
primary\0some-var-len-region-name\0max_region_key          10

If a column in the PK is variable length, Phoenix expects it to be null terminated. Are region names variable length too?

One thing we'd be after is to be able to query the stats table through Phoenix. It'll definitely make debugging and troubleshooting easier.