Re: Optimizing sum() operations

> This is a just a general theory that occurred to me, it's probably a
> pretty specialized kind of indexing that isn't supported by any RDBMS,
> but it's possible there could be a postgres plugin which did this,
> though.  Has anyone heard of something like that?

The problem with this is that there's generally more than one metadata
field for each key set - and frequently you might want to sum or max
each value.  I think the value of having this kind of structure would be
quickly mitigated by virtue of increasing node size and slowing node
retrieval times.

> I think that if there are a lot of rows that match the query, it'll
> take a long time, so I thought I'd start inquiring about whether
> anyone has a good algorithm for accelerating these kinds of queries.

The best solution that I've found for things like this is to look to
data warehousing: if you have a frequently used aggregation of facts,
then preaggregate (summarize) it and pull from there instead.

-Mark