Patent ID: 7143099

Claim:
A method used in a computer system for creating from operational data an historical data warehouse containing subject-oriented data, comprising: a) obtaining operational data from a source system; b) pre-processing said obtained operational data by a stepwise operation, wherein only the last operated upon data is recorded such that data recording is avoided during data addition for efficiency purposes; c) transforming said pre-processed data into subject-oriented data by utilizing reusable primary keys and Relational Database Management System dates in an operating system of the source system to link related pre-processed data; and d) storing said subject-oriented data in the historical data warehouse; wherein said dates within said Relational Database Management System in said operating system of said source system are obtained by trigger or log-scraping of said Relational Database Management System; wherein said pre-processing includes an insert function that returns a warning when associated subject-oriented data already exist in said historical data warehouse; wherein said Relational Database Management System dates are utilized for distinctly characterizing said subject-oriented data when a plurality of tables containing operational data with duplicate primary keys are combined in said historical data warehouse; wherein said subject-oriented data is stored in said historical data warehouse with an associated creation data and deletion data derived from said Relational Database Management System dates.