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Operational vs Dimensional Databases, and XML.

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1. What are the differences between the characteristics of an operational database and a dimensional database?

2. What is XML, and why is it useful?

3. What is an XML Schema document?

4. How can XML be used with a DBMS?

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1. What is the difference between the characteristics of an operational database and a dimensional database?

An operational database contains enterprise data that are up to date and modifiable. This type of database usually uses an OLTP database which is optimized for faster transaction processing such as insertion, deletion and update of data. It is the database that is currently and progressive in use capturing real time data and supplying data for real time computations and other analyzing processes.

A dimensional database is the one that rather than representing data in multiple relations, represents key data entities as different dimensions. Which means that, multidimensional database systems offer an extension to the relational system to provide a multi-dimensional view of the data. A dimensional database needs to be designed to support queries that retrieve a large number of records and that summarize data in different ways.

The difference between the characteristics of an operational database and a dimensional database are illustrated in the following table:

Operational Database:
Data is atomized
Data is current
Processes one record at a time
Process oriented
Designed for highly structured repetitive processing

Dimensional Database:
Data is summarized
Data is historical
Processes many records at a time
Subject oriented
Designed for highly unstructured analytical processing

2. What is XML, and why is it useful?

XML stands for eXtensible Markup Language. XML is a meta-markup language developed by the World Wide Web Consortium (W3C) to deal with a number of the shortcomings of HTML. It defines a set of rules for encoding documents in a format that is readable by both human and machine. The design goals of XML emphasize ...

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