1) A data warehouse is a collection of data from multiple sources used to enable informed decision making. It contains data, metadata, dimensions, facts and aggregates. 2) The typical processes in a data warehouse are extract and load, data cleaning and transformation, user queries, and data archiving. 3) The key components that manage these processes are the load manager, warehouse manager and query manager. The load manager extracts, loads and does simple transformations on the data. The warehouse manager performs more complex transformations, integrity checks and generates summaries. The query manager directs user queries to the appropriate data.

1. Data-ware Housing

2. Introduction

3. Definition : Simplex perception- No more than collection of Key pieces of information used to manage & direct the business for the most profitable outcome. Precise Definition- It concentrate on data- Data should be subject oriented, be consistent across sources & so on. Pearson’s Definition- It is more than vast data- it is also process involved in getting that data from source to table & from table to analyst’s. ** In other word ** “ A DWH is the data (Meta/fact/dimension/aggregate) and process manager (load/warehouse/query) that make information available, enabling people to make informed decision.

4. Data-ware housing Architecture : DWH must architected to support three major driving factors. 1) Populating DWH. 2) Day-to-Day management of DWH. 3) The ability to cope with requirement evolution.

5. Typical Process flow within D.W.H Source Extract & load Warehouse Data transformation and movement User Query Archive data

7. Extract & load process: Op. Data Suitable for operational System, May have been modified & extended over yr’s to support performance. D.W.H Reconstructed

12. 4) Query management process : Directing query to most effective data source.

13. Process Architecture

14. Process Function System manager Extract & load Extract & load the data, performing simple transformations before & during load. Load Manager Clean & transform Data Transforms & Manages data Warehouse manager Backup & archive Backs up & archives data warehouse Ware house manager Query Manager Directs & manages queries Query Manager

15. Operational Data Operational Data L O A D M A N A G E R Detailed information Summary info Meta Data Q U E R Y M A N A G E R Warehouse Manager Data dipper OLAP tools Data Information Decision Architecture of data-ware house

21. Load Manager Architecture File structure Temporary data Store Ware house str. Load Manager Controlling Process Stored Procedure Copy management tools Fast loader

24. Ware house Manager Architecture Temporary data store Star flake schema Summary tables Ware-house Manager Controlling Process Stored Procedure Backup /recovery tool SQL scripts

26. Complex Transformation Reconcile data