Open source vs not open source. Cockroach still in it's infancy vs spanner. I'm sure there are a variety of things here, but they mostly aim to solve a similar problem with a slightly different approach.

Some of the big details relate to not requiring atomic clocks: https://www.cockroachlabs.com/blog/living-without-atomic-clo...

Here's their comparison chart, though naturally it's biased for things-cockroach-does: https://www.cockroachlabs.com/docs/cockroachdb-in-comparison...

(I guess you can't write to Spanner with SQL? That seems like a big difference. No INSERT/UPDATE?)

I'm confused. What's the difference between 'Yes' and 'Optional' in the 'Commercial Version' row on the comparison chart? To me 'Yes' suggests there is only a commercial version, but clearly that's not true for CockroachDB.

Thanks for pointing that out! We will fix that to optional for us :)

[cockroachdb here] Thanks for the great response, bpicolo!