[bradleyland]

That's your preference, but I've not often found an occasion were someone (a client/stakeholder) said, "Yeah, go ahead and give that to me slower rather than faster." It just never seems to happen.

I'm thinking of this as something like polyglot memoization. Pretty cool when you think about it. Frequently need something that is slow in NoSQL, but fast in SQL? Memoize it to your SQL datastore. The alternative has always been to write it to two places. I kind of dig moving this out to the datastore to figure out.

I'm thinking that plenty of people will find this useful.

[physcab]

That's why I'm curious what sort of questions they are answering with this tool. If the bulk of their questions are a variant of SELECT COUNT(DISTINCT user_id) FROM table, then yes, this would be convenient to have. But if their questions start to revolve around transaction cohorting or path analysis where there are potentially hundreds of millions to billions of transaction_ids with some gnarly JOINs thrown in for good measure, I would be surprised to see this scale.