Update/Refresh stratergy

[coolspartan]

Hello Gurus,
I have a requirement for an aggregate table loading by week. The requirement specifies that the aggregations should be calculated for a week, every week. And every week the previous weeks should be refreshed as records for the previous weeks change. My question is.... should I delete all the records from previous weeks and calculate and populate them again? Or should I treate rows as "update" in the source and load them by treating them "update else insert" in the target? Or is there any other way that I should procede to fulfill this requirement.

Thanks in advance,
Spartan

 

[blom0344]

Regular approach for aggregate tables is to rebuild them again, especially if older data can still change.
Imagine that certain changes would cause a specific key to dissappear in the output. This will never be properly handled with an update strategy that you decribe.....

Ties Blom
Information analyst
tbl@shimano-eu.com