On Tue, 16 Apr 2019, Dan Smith wrote:
So, for the sake of making it explicit, what's wrong with:
* add a nullable shard column * enable the openstack-shard header I suggested at the last ptg [1] * let deployments start using that, but only if they want to. If they do all rp writes and queries use it.
This sounds like a trap, so I'm curious... What, um, is left in such a feature beyond this? :)
Sorry, no trap intended. I had recalled that you had a preference to not null and I couldn't remember the reasons. [snip]
I'm not crazy opposed to everyone being in the undeclared null shard until they need to be in something else. I don't prefer it because:
- I think it will be better tested (and test-able) if it's not optional - It's an identifier, and we'd never say "we don't need a non-null row id column until later when we need it" - I think that other services that may start reporting to or using placement may just omit that part in early development
For completeness, your preference would be something more like the way we do incomplete project and user for allocations that pre-dated consumers? Make an explicit default (and configurable) shard uuid and migrate to that? -- Chris Dent ٩◔̯◔۶ https://anticdent.org/ freenode: cdent tw: @anticdent