salam
This topic was
very interesting. First of all I learnt that database is a mechanism for storing, managing and retrieving
information. Therefore, I can say that the man function of database is to
store, organize, and control data. Database has two components which are data
item and schema. Data item is a field in data processing and it is a
piece of information. However, schema describes the organization of data and
the relationship within the database. The schema consist several types of
record in database and the data items sets into which they are grouped. The
architecture of database consists of the actual database, hardware to process
and store data, software to manipulate the contents, and people to access,
control, and use the data. After that, I learnt about Database Management System
(DBMS) which can be defined as a software package for manipulating databases or
it can be called as database program. The examples of DBMS are Microsoft Access and
FileMaker. In addition, DBMS has some features such as allow users to create
new databases, give users the ability to query and modify the data using
appropriate language (query language or data manipulation), and it provides
information by using Structured Query Language ( SQL) to decision makers to achieve important
decisions. I also learnt three types of languages which are Data Definition
Language (DDL), Data Manipulation Language (DML), and Structured Query Language
(SQL). Then, I learnt DBMS components which are field, record, table, key
field, relational database, and objects. The first components is field
represented by column describes a specific piece of category such as first name,
last name, or city. The second component is record represented by row and it is
a group of related data about a person, place or anything. The third component
is table (entity) represented a collection of records for a single subject such
as students or products. The fourth component is key field represented a field
that contain a unique information for each record such as student ID for a
student. The fifth component is relational database represented multiple tables
which are linked together to address a business process such as courses and
students. The last component is objects which help the users to edit, manage,
and analyze the data. Moreover, I learnt that data models use three types of
relationships which are One to One (1:1), One to Many (1:M), and Many to Many
(M:N). In One to One relationship each row in database table is linked to only
one row in another table. For example, one person can only have one passport AND one passport is belonging to
one person.
In One to Many relationships, each
row in related table can be related to many rows in relating table. For
example, mother can have more than one child.
. 
In Many to Many relationships, one
or more related rows can be related to many rows in relating table. For
example, students and subjects; one student can registered many subject and one
subject can be registered by many students.
After that, I learnt three types of
users in DBMS who are end users, application programmers, and database
administrator. Then, I learnt about database models which can be defined as
structure, characteristics, description, and organisation database. Database
model can be also called as dictionary database. Database models have several
types such as hierarchical database, network database, relational database, and
object-relational database. Hierarchical model was developed by IBM Company in
1960s. It organizes data in a tree structure (upside-down tree). It may also
use one to many relationships. However,
network database is improvement from hierarchical model. Data in network
database are represented by records suing links among them. Therefore, it is
created for complex data relationship and it uses many to many relationships.
In relational data model, data is organized in the form of rows and column in
tables.The relational data model is
implemented through a sophisticated relational database management system
(RDBMS) and it is useful for small database system.After that, I learnt the types of database
which are individual, company or shared stored on a mainframe by a computer
professional, and distributed stored in several locations. At the end our
lecturer gave us a quiz in this topic to see our understanding.
Thank You
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