What is a database? How is the data stored?

1. Database

2. What is a database?
• A database is a collection of information
organised in a tabular format in the form of
rows and columns. You can create database
using Database Management System (DBMS).

3. RDBMS
• RDBMS refers to DBMS that stores data in the
form of tables that are connected with each
other in the database.

4. What is data type?
Data type refers to the type of data which
can be stored in a column of a table.

5. Different Data Types
• Text: Stores short alphanumeric values, such as numbers, text
or a combination of both.
• Memo: Stores substantial alphanumeric text, such as notes
and descriptions.
• Number: Stores numeric data for arithmetic calculations. A
number can be either positive or negative.
• Date/Time: Stores date and time values, such as Date of Birth
and Date of Joining.
• Currency: Stores currency values like the price of a product.
• Yes/No: Stores Boolean values, such as Yes/No, True/False and
On/Off.

6. Row and Column
• A row or records represents a set of related
information about a particular entry in a table.
• A column or field represents a category of
information or data value, related to all
records.
Column 1 Column 2 Column3 Column n
Record 1
Record 2
Record n

7. Uniquely Indentify Record
• A Primary Key is a column in a table which has
unique values. It cannot contain NULL or blank
values. A table can have only one column set
as Primary Key, which is used to identify a
record.
UID Column 2 Column3 Column n
001
002
003

8. Data
• Data of different type related to an entity is
stored logically.
• Entity could be a user, product, service, etc.
• Data includes different characteristics related
to entity.

9. Why is it important?
• To get the required information at the time of
need
• To analyse various aspects of entity. For example:
– Learning pattern
– PII- Personally Identifiable Information
– Progress report
– Learning outcome
• To inspect and improve weak points
• To better cater to user needs

10. How to define?
• Database Schema
– Logically
– Physically
– Conceptually
• Database has tables
• Tables have rows and columns
• Rows and columns have data inside them

11. For more tutorials and courses please visit:
www.codewizacademy.com