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Databases And Data Warehouses

Databases and Data Warehouses

1. How are data represented?

Data are raw materials used to produce information.

It is any facts, text, and other multimedia objects that we are interested in capturing and storing.

Information is data that have been processed in such a way that it can increase the knowledge of the person who uses it.

Data Representation
a) Field – The smallest unit of data that has meaning to humans.
b) Record – Collection of fields that contain information concerning specific thing or event.
c) File - A collection of records.
d) Database – A group of related files


2. What is business intelligence and its role?

Business intelligence is knowledge about your customers, your competitors, your partners, your competitive environment, and your internal operations that gives you the ability to make effective, important, and strategic business decisions.

IT tools help process information to create business intelligence according to:
a) OLTP – gathering of input information, processing that information and updating existing information to reflect the gathered and processed information. Databases and DBMS support OLTP. (Operational database)
b) OLAP – manipulation of information to support decision making. Data warehouses and data mining tools support OLAP.

3. How are transactions recorded and processed.

Transaction – A record of an event.

Processing – Procedures to store, retrieve, and manipulate records of events.

Traditional file processing system:
1. Two files
• Master file – relatively static data is stored
• Transaction file – information relevant to the most recent transaction is stored.

2. Batch processing
• Data grouped together and processed at some point after original transactions occurred.
• Data written on paper/off-line, and captured electronically later ; records assessed in sequential order.
OLTP:
1. Data captured directly/online and processed immediately.
2. Real-time processing: a...