Database is used to store the transaction data in the form of normalized tables. In Data Warehouse also we preserve the data but the data is in a summarized form, historical data is preserved and Non Volatile.This features makes the Data Warehouse is fit for preparing Decision making system /Business Intelligence System.
Data Warehouse is also differs from normal database in terms of Data Model, Data Maintained, Performance etc., .
- In general normal database follows Relational Database Model System (RDBMS).All the tables are inter related with the aid of Primary key and foreign key. Where as in Data Warehouse it follows a data model structure like Star Schema / Snow Flake Schema / Galaxy Schema .Here we observe Dimension and Fact tables whicha are in denormalized form.
- Normal Database holds the current transaction data only. Here the data can be deleted, Modified , inserted .This makes the Normal Database is unfit for preparing BI systems .In Data Warehouse one can meet the goals of BI system by holding the historical data , Non Volatile process.
To make clearer, let's look at the following lines … In general a normal database holds all the attribute values presented in the table. These records assist the customer and low level professional of an organization. This data is not useful for Higher Level officials/Business Analyst since they are not bothered about all the attributes presented in the table. They always expect the Business measure values and necessary contexts related to it to be presented in the table and also historical records of it. This makes them to compare the values and take necessary business forecast to meet the business strategies.
DATABASE |
DATA WAREHOUSE |
Current Data |
Historical Data |
Useful to Customer / Low Level Officials |
Useful to CEO, Business Analyst |
Every company must maintain a database. |
Mid and High Level Organizations |
Now you where comfort to answer the Question “How a Data Warehouse is different from Database” … But I know you are curious to know how a Data Warehouse was developed? Well this can be achieved by implementing ETL and Reporting process. End user no need to right any queries to access the analytical data. And can view the data as reports with a single click. There are many Data Warehouse tools available in the market .You can choose any of the one which matches to your budget and requirement.
ETL Tools: Informatica , Datastage, Oracle Warehouse etc.,
Reporting Tools: Business Objects, Cognos , Microstrategy etc.,
The cost of Data Warehouse development is higher than normal database. That's why Data Warehouse used only by those companies
- More number of customers all over the world :: Banking, Telecommunication, Health Care Sector ,Government Sectors
- More number of products :: Manufacturing companies
- More number of employee :: IT sector
| Author |
Mr.Lakshman is a Young BI professional , eager to acquire good knowledge on Data Warehouse Tools .
His recent look at "Data Vault -- material available on WWW". |
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