What's the best way of producing stats of my data

Data:

10000 records changing daily

10 different users

Important to get immediate update of the stats

1. Statistic summary field in db1 - showing on layout with db2 through user relationship

2. Calculation in db2 - sum(db1::time)

I'll try to answer the question myself then...

I'm almost sure that the sum(relationship::field) is the best one, but it's a bit slow, are there a better one? Could a sum field made in DB1 and shown in DB2 be faster?

Unless you script the update to set a static related field with the Sum result whenever a time field is changed, Sum(rel::field) is your best option.