Processing methodology

we have 3 large fact tables with combined rec cnts of 32 million. These 3 fact tables share order attribute that we would like to pull out and create a order dimension so that the facts tables don't have to contain the attributes. I've tried update processing of this dimension but the time it takes is not much different than a full process. I would like to know if there is anything like a incremental processing of this dimension and how would I set that up?

I assume that you are using Analysis Services 2005?

Actually, the "Process Update" method is slow than doing a "Process Full" on a dimension. The reason for this is, that "Process Update" reads the entire dimension table and compares the content of this with the existing, processed dimension. Any differences are then updated in the OLAP dimension. "Process Full", on the other hand, does not have to make any comparisons - it simply reads the entire dimension table and builds the OLAP dimension.

Now, the main reason for using "Process Update" is that is does not invalidate your processed measure groups. If you do a "Process Full" on the dimension, you are forced into doing a "Process Full" on any measure group that contains this dimension. Note, that "Process Update" will invalidate the aggregations on any associated measure group, provided that changes have occured to the dimension. This means, that a "Process Update" on the dimension will have to be followed by a "Process Index" on the associated measure groups in order to get aggregations back.