Data Granularity

n      What is Granularity of your DW?

q     Granularity is the level of details we want to store in the data warehouse.

q     For a retail store, Point of Sale (POS) is the lowest granularity information available.

q     For banking its the account level details based on every day transactions.

q     As DSS is learning towards analyzing the data as a whole, not necessarily the data warehouse will have all the details up to daily transactions.

n      Daily sales by date, product and customer

n      Weekly sales by product and customer

n      Monthly sales by product and customer

n      Quarterly sales by product and customer

n      Yearly sales by product and customer

n      Usually in Data Warehouses (EDW) we will tend to have POS where as in Data marts we will have it aggregated by week or month so that we never loose the detailed information. This detailed level data can be used to get the micro behaviors of our customers (especially in Data Mining)