🔖 The 'Simulator for Database Aggregation using Metadata' addresses the problem of hardcoded end-user applications by sitting between the end-user application and the DBMS, and intercepting the end user's SQL. With a Simulator for Database Aggregation using metadata, the end-user application now speaks "base-level" SQL and never attempts to call for an aggregate directly. Using metadata describing the data warehouse's portfolio of aggregates, the aggregate navigator transforms the base-level SQL into "simulator-aware" SQL. The end user and the application designer can now proceed to build and use applications, blissfully unaware of which aggregates are available.