beginner question

Hi, folks:
I am looking into using SSIS to create a OLAP database. How easy it is to write a package to re-pull some fact data from the source databae base on some flags. What happend is we are planning to roll up some minute by minute data into hourly averages using SSIS but user is allowed to modified the minute by minute data (maximum is 90 days). Say if we set up some flags, and the package comes in every hour to check for these flags and only re-ETL the changed one. Can I be done or is there better way to do it.SSIS can push data straight into an OLAP cube from the pipeline. I'm not sure about updating values that are already there though (if that is what you are asking).

-Jamie|||Yes, that's updating the OLAP values is what I am asking. We do gas-flow calculation. For each well, we insert minute-by-minute data. Out of a thousand wells, only 10 wells will have the minute by minute data changed, and all I plan to do is to flag these 10 wells and re-ETL them.