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Data: any raw facts or figures that can be recorded or stored.


Information: when data are processed, organized to make meaningful or usable.


Database: collection of related data.


Types of database:


1. Traditional Database: it contains text and number.

Explore more about traditional Database:

a. dbms-vs-traditional-file-system

b. traditional_db


2. Multimedia Database: it is a collection of related multimedia data. Multimedia data include images, songs, videos etc.

Explore more about Multimedia Database:

dbms-multimedia-database


3. Geographic Information System (GIS): It designed to capture, store or manipulate the geographical data.

Explore more about GIS:

Geographic_information_system


4. Data Warehouse: it stores large amount of historical data.

Explore more about Data Warehouse Database:

difference-between-a-database-and-a-data-warehouse


5. Others: Types-of-databases


Database Management System (DBMS):

It is a program for create and manipulate database. It provides systematic way to create, retrieve, update and delete data.


Database system = database + DBMS


Database basics: Introduction to DBMS


Advantages and Disadvantages of DBMS:

a. dbms-vs-file-system

b. Video: Advantages of DBMS over File System


OLAP vs OLTP:


1. oltp-vs-olap

2. dbms-olap-vs-oltp

3. Video on OLAP vs OLTP: OLAP vs OLTP


OLAP
OLTP
Stands for Online Analytical Processing.
Stands for Online Transaction Processing.
It uses the Data Warehouse.
It uses Traditional DBMS.
Mostly select operations
Insert, Update, Delete data from the database.
Response time is seconds to minutes.
Response time is in milliseconds.
Mainly Read operations are performed
Allows Read/Write operations.
It is subject oriented
It is application oriented.



Database Architecture:

1. dbms-architecture

2. concepts-of-database-architecture


Database Model/ Degree of Data Abstraction:

It determines the logical structure of a database and in which manner data can be stored, organized and manipulated.


Database model in detail: data-modelling-conceptual-logical


1. High Level Model/Conceptual Model:

This defines What the system contains. In this we use some diagrams (e.g. ER diagram). It defines the scope of information and the main purpose is for communication and agreement of context.


2. Logical/representational/Implementation Model:

This defines the How the system should be implemented. Relations (Tables) are used at this level. This model mainly used by Programmers. Main purpose is for communication and agreement of business logic.


3. Low Level/ Physical level Model:

This defines the How we access the data. It is the physical representation of the database. Physical model has the lowest level of the abstraction.

 
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