Database 101

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Noor Aliah Syafirah binti Khairur Anuar
Nor Zaliah binti Abdullah
Nur Edleen Fatma binti Che Azhari
Nur Najwa Imani binti Abd Hadi
Radin Nur Haziqah Binti Radin Abdul Aziz
Syarafana Diyanah binti Shaharudin
Muhammad Hazeem Shah bin Shafudin
Nur Aisyah binti Jabar
Nur'Eka Khairunnisa binti Hairudin
Nurafifah Syazwani binti Jasni


Hello everyone! For today, we would like to share about a topic that is a part of our syllabus in Introduction to Information Technology, which is Database and Information System.

Often, we heard about the term "database", especially for those taking courses relating to Information Technology (IT). But, what exactly is a database? What makes it something that is used widely in various fields nowadays?

A database (DB) is a collection of data which is organized. More specifically, a database is an electronic system that allows data to be easily accessed, manipulated and updated.

In other words, a database is used by an organization as a method of storing, managing and retrieving information. Modern databases are managed using a database management system (DBMS).

Software programmers are well acquainted with database concepts through relational databases like Oracle, SQL SERVER and MySQL, etc. Typically, a database structure stores data in a tabular format.
An example of a database in our everyday life would be any online streaming services, such as Netflix. It uses databases to generate a list of TV shows and movies for users to watch. The database also keeps track on an individual's show preferences. From there, they will also generate a list of recommended shows for users to view.

There are four types of database, which are:

• Hierarchical databases
• Network databases
• Relational databases
• Object-oriented databases

1. Hierarchical database

                               

• A parent-child relationship of storing data.
• People rarely use this type of database nowadays because of the structure does not support multiple data storage
• Its structure is like a tree, with nodes representing the records and branches representing fields.

           

       2. Network databases

        

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3     3. Relational databases

• ·        Defines database relationships in form of tables , also known as relations . Unlike network DBMS , RDBMS does not support many to many relationships.
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•         Relational DBMS have predefined data types that they can support . Connect to the data in different files by using common data numbers or a key field.

•          Examples of relational database management systems include MySQL , Oracle and Microsoft SQL Server database
•         Data in relational databases is stored in different access control tables , each having a key field that mainly identifies each row.
•       Reliable tables or files filled up with data are called relations (tuples) designates a row or record , and columns are referred to as attributes or fields.
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Object oriented databases

• ·        Support storage of new data types.
  ·        The data to be stored is in form of objects .
  ·        The objects to be stored in the databases have attributes (i.e. gender , ager) and methods that define what to do with the data.
  ·        PostgreSQL is an example of an object oriented relational DBMS.

                  

•        Object oriented databases use small, recyclable separated of software called objects.
•        The object themselves are stored in the object oriented database. Each object contains two elements.

-        Piece of data (e.g. sound, text, or graphics)

-        Instructions or software programs called methods, for what to do with data.

What is SQL?

v  SQL is Structured Query Language.

v  SQL is an ANSI (America National Standards Institute) standard language, but there are many different version of the SQL language.

v  SQL is a computer language for storing, manipulating and retrieving data stored in a relational database.

v  SQL programming used to insert, search, update and delete database record.

v  SQL is a standard language to dealing with Relational Database System.

v  Example Relational Database Management System use SQL as their standard database language

   1) MySQL

   2)MS Access

   3)Oracle

   4)Sybase

   5)Informix

   6)Postgres

   7)SQL Server

        DATABASE AND INFORMATION SYSTEM

1    What is Database?

-        Database Management System (DBMS) is an organized collection of data that can be easily accessed, managed, and updated.

-        Data is organized into rows, columns and tables and it is indexed to make it easier to find relevant information.

-        The rapid growth of big data creates unprecedented demand and opportunities for developing powerful intelligent information systems that help people manage and extract knowledge from data.

2      File processing:

-        Information was stored using File Processing System before DBMS was invented.

-        In this system, data is stored in permanent system files (secondary storage)

-        It is traditional files system stores data in a manner that all the departments of an organization have their own set of files that creates data redundancy.

3      Disadvantages of File Processing

a      a. Data redundancy:

-        Duplicate data in the system is not appreciated as it is a waste of space, and always lead to confusion and mishandling of data. When there are duplicate data in the file, and if we need to update or delete the record, we might end up in updating or deleting one of the record. Again, the file system does not validate this process. Hence the purpose of storing the data is lost.

        b.     Isolated data

-        Different files may have different formats and these files may be stored in formats (directories) may be of computers of different applications.

-        Sharing data from multiple, separate files is a complicated procedure.

Click here : the components of Information System

   types of Information System

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