· data organised in the form of tables.

·     
Relational
Database:

A Relational Database or RDB is a
collection of many sets of data organised in the form of tables. The relation
among these tables could be inferred as Relational databases. The tables have
records, where each record is identified by a field containing a unique value.

In the database, every table has a connection with other table in “one-to-one”,
“one-to-many”, “many-to-one” and “many-to-many”.

 

·     
Role
of the relational database in an organization today

Any type of organisation, whether
business or personal, live or die on the accuracy, performance, and reliability
of their databases in today’s world. Every organisation depend on the accurate recording, updating and tracking of their data
on a minute-to-minute basis. Employees use this data to complete accounting
reports, calculate sales estimates etc. where they can have access to database.

 

·     
Characteristics
of a Relational Database:

o   The use of keys – Each row of data in a table is identified by the use of unique key
called the “primary key”. Data in different tables can be linked together
using keys. The primary key values of one table can be added to rows of a
different table, thereby linking those rows together.

o   Avoiding Data Redundancy – Same data that is stored under in multiple
locations.

o   Constraining the input – Database systems allows to use data types and also
different types of constraints like length, uniqueness etc.

o   Maintaining data integrity – By setting field properties, by linking tables and by setting
constraints you can increase the reliability of your data.

o   Rights – Operations that can be allowed or
disallowed to a user are SELECT, INSERT, DELETE, ALTER, CREATE, etc. These
rights correspond to the operations that can be performed using the Structured
Query Language (SQL)

o   Portability – Transfer of data from one place to
another without effecting the actual data.

 

Article- http://en.tekstenuitleg.net/articles/software/database-design-tutorial/database-characteristics.html   (date visited- 24/01/2018)

 

·     
Main
functions of the Relational Database Management System (RDBMS):

o   Normalisation – Database normalization
is a process by which an existing schema is modified to bring its component
tables into compliance with a series of progressive normal forms. The concept
of database normalization was first introduced by Edgar Frank Codd in his paper A Relational Model
of Data for Large Shared Data Banks, section 4

o   Modifiable – New rows and columns can be
added or removed.

o   Fast processing.

o   Fast retrieval of data  

 

 

·     
Importance
of database designs.

The database design is very important for efficiency. The consistency of
the data in the database is achieved when only useful and required information
is stored. Storing the data will be ease. The goal of a good database is not just to store data, but
ultimately the extracting or retrieving of information to support decision
making by an individual, or groups of people in the organization. A database
which is designed efficiently is a foundation of successful information system.