Is there any API to dump the size of a relation rather than the whole content?

[enochii]

Hi, really excellent work!

I wonder if there is any API to dump the size of a relation rather than the whole content, say, at the end of a transaction? It seems like there is no such API according to the command reference.

[mihaibudiu]

One way this can be done is by creating (ahead of time) a relation (view) that maintains the size of another relation (using aggregation) and querying that one.

Please note that this project is now archived. There is a follow-up project at https://github.com/feldera/feldera

[ryzhyk]

An aggregate view may not be a good solution, esp. for production use due to the overhead. I would recommend using the profile command, which will output the size of all in-memory indexes maintained by the program. It's too expensive to call on every transaction, but you can call it once in a while.

[enochii]

Thanks a lot for the kind reply!

I am not so familiar with Datalog. Just curious, I wonder why no such API provided, it seems quite natural from my perspective since we already have APIs to dump the content of relations. Is it due to performance issue?