Information from several sources.
WHAT MAKES IT DIFFICULT
Different structures Different definitions Different timing Identifiers that do not match
WHY DEFINITIONS CAUSE MOST DISPUTES
Revenue, customer and active mean different things in different systems.
WHAT TO ESTABLISH
Agreed definitions, documented, with an owner.
WHAT A DATA WAREHOUSE PROVIDES
Data from several systems, structured for reporting.
WHAT IT REQUIRES
Extraction, transformation and loading Ongoing maintenance as sources change
WHAT IT PROVIDES BEYOND CONVENIENCE
Reporting without loading operational systems History preserved as sources change Consistent definitions applied once
WHAT SIMPLER ALTERNATIVES EXIST
Reporting tools reading several sources directly Scheduled extracts into a shared location
WHAT TO CHOOSE
The simplest supporting the questions actually asked.
WHAT TO ESTABLISH ABOUT TIMING
Whether reports reflect the same moment across sources.
WHY
Data extracted at different times does not reconcile.
WHAT TO DISPLAY ON EVERY REPORT
When the data was extracted.
WHAT TO RECONCILE
Any warehouse figure against its source.
WHAT TO DO WHEN THEY DIFFER
Investigate before publishing.
WHAT TO AVOID
Several reports of the same measure, differing.
