2. Topics to be covered
“what is a database;”
Understand the difference between data and
information;
What is the purpose of a database system;
Database definitions and fundamental building
blocks;
2
3. What is a database
A database is any organized collection of data. Some
examples of databases you may encounter in your daily
life are:
a telephone book
T.V. Guide
airline reservation system
motor vehicle registration records
Forms you are filling for Admission
3
4. Data vs. information:
What is the difference?
What is data? What is information?
Information is data that have
Data can be defined in
been organized and
many ways. Information
communicated in a coherent and
science defines data as
meaningful manner.
unprocessed information.
Data is converted into
information, and information is
converted into knowledge.
Knowledge; information
evaluated and organized so that
it can be used purposefully.
4
5. What is the ultimate purpose of a
database management system?
Is to transform
Data Information Knowledge Action
5
6. Why do we need a database?
Keep records of
Students
Staff
Library
Stocks
To keep a record of activities and
interventions;
Keep sales records;
Develop reports;
Perform search
Tracking a particular record
6
8. What is the purpose of the
database ?
• A database management system (DBMS)
provides you with the software tools you need to
organize that data in a flexible manner.
• It includes tools to add, modify or delete data
from the database, ask questions (or queries)
about the data stored in the database and produce
reports summarizing selected contents.
8
9. Some Important Definitions
A File: A group or collection of similar records, like Student File,
American History 1850-1866 file, Basic Food Group Nutrition File
A field: one category of information, i.e., Name, Address, Semester
Grade, Academic topic
A record: one piece of data, i.e., one student's information, a recipe, a
test question
A layout: a design for a database that contains field names and
possibly graphics.
9
10. Fundamental building blocks
Tables comprise the fundamental building blocks of any database. If you're familiar with
spreadsheets, you'll find database tables extremely similar. Take a look at this example of a
table sample database:
The table above contains the employee information for our organization -- characteristics like
name, date of birth and title. Examine the construction of the table and you'll find that each
column of the table corresponds to a specific employee characteristic (or attribute in database
terms). Each row corresponds to one particular employee and contains his or her
information. That's all there is to it! If it helps, think of each one of these tables as a
spreadsheet-style listing of information.
10
11. What is Microsoft Access Used
For?
Microsoft Access is an information management tool
that helps you store information for reference,
reporting, and analysis. Microsoft Access can help you
overcome the limitations found when trying to
manage large amounts of information in Microsoft
Excel or other spreadsheet applications.
11
12. What is Microsoft Access made up
of?
The Microsoft® Access Database is made up of 7 major
components:
Tables;
Relationships;
Queries;
Forms;
Reports;
Macros;
Modules.
12
13. Tables
The tables are the backbone and the storage container
of the data entered into the database.
The tables that contain data look a bit like a table in
Microsoft® Word or a Microsoft® Excel Spreadsheet,
when opened. They have columns and rows as does a
table in Microsoft® Word and an Excel worksheet.
Each of the columns will have a field name at the top
and each of the rows will represent a record.
As an example:
Sl. No. Name Marks
1 Ratan 89
2 Mahima 90
3 Nisha 70
13
14. Primary Key
The primary key of a relational table uniquely identifies each
record in the table.
This can be a unique identification number such as a Medicare
number, Employee ID number, Pension number, etc.:
A primary key cannot contain duplicate values, e.g. a person’s
last name is not suitable as a primary key as there is often more
than one person with the same last name;
A primary key cannot contain null values, therefore a field such
as a phone number is not suitable, as you may not know the
person’s phone number when you first enter them into the
database;
Also, if the information contained in the Primary Key is likely to
be altered, then it is best to avoid this field as well.
If a unique identifier cannot be identified (which is more than
likely), you can add a field, which will automatically increase
sequentially by one, thus providing the record with a unique
identifier.
14
15. Data type
The data type of a programming element refers to
what kind of data it can hold and how that data is
stored. Data types apply to all values that can be stored
in computer memory or participate in the evaluation
of an expression.
Example
Name – hold alphabets
Marks – number
15
16. MS ACCESS DATATYPES
AutoNumber Numbers that are automatically generated for
each record.
Currency Monetary values.
Date/Time Dates and times.
Hyperlink Hyperlinks, such as e-mail addresses.
Memo Long blocks of text and text that use text formatting. A
typical use of a Memo field would be a detailed product
description.
Number Numeric values, such as distances. Note that there is
a separate data type for currency.
OLE Object OLE objects, such as Word documents.
Text Short, alphanumeric values, such as a last name or a street
address.
Yes/No Boolean values.
16
17. You can view your Microsoft Access tables in two
different views - Datasheet view and Design view.
Datasheet view : Access allow you to view the contents of a
table. When opened, you will see something similar to a
spreadsheet, with columns of data with the field names
identifying each column, whilst each row is a single record
within the table. This is called the datasheet view.
'Design view' where you see the structure of the table
rather than the contents. It shows the field names and their
datatype. From design view you can add and delete fields
within the table, although you have to be careful with
deleting the primary key in the table as that would cause
problem with data integrity.
17