The document provides an overview of databases, including their purpose, advantages, and disadvantages, as well as types of keys and database languages. It explains that databases serve as repositories for data that can be retrieved and modified to support organizational functions. Additionally, it discusses the role of database management systems in ensuring data integrity, consistency, and durability.

1. Introduction to Database
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2. Lecture No 2
Overview of Database
By
Engr. Muhammad Anwar
anwarreki2016@gmail.com
Lecturer at Computer Science Department
University of Turbat (Panjgur Campus)

3. Sahih al-Buk
hari 59
Book 3,
Hadith 1
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4. Lecture
Outline
Introduction to Database
Database Concept
Purpose of Database
Advantages of Database
Disadvantages of Database
how does the database accomplish this purpose?
keys in a database
Database Languages
Types of Database Languages
purpose of database software
Is Excel Database System?
Tip of the Day
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5. Database Concept
A database intends to have a collection of data
stored together to serve multiple applications as
possible. Hence a database is often conceived of as
a repository of information needed for running
certain functions in a corporation or organization.
Such a database would permit not only the
retrieval of data but also the continuous
modification of data needed for control of
operations. It may be possible to search the
database to obtain answers to queries or
information for planning purposes.
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6. Purpose of
Database
Introduction to Database
The purpose of
a database is
to help people
keep track of
things.
It accomplishes
this purpose by
storing data in
tables.
Each table has
rows and
columns, like a
spreadsheet.
A database
usually has
multiple tables
in order to
keep track of
different but
related things.
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7. Advantages of
Database
Introduction to Database
Better Data Transferring
Better Data Security
Data Abstraction
Controlling data redundancy
Minimized Data Inconsistency
Faster data Access
Better decision making
Increased end-user productivity
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8. Disadvantages
of Database
Introduction to Database
Cost of hardware and Software
Cost of data conversion
Cost of Staff training
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9. keys in a database
 A key in DBMS is an attribute or a set
of attributes that help to uniquely
identify a tuple (or row) in a relation
(or table).
 Keys are also used to establish
relationships between the different
tables and columns of a relational
database.
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10. Type of Keys in
DBMS
1. Primary Key
2. Candidate Key
3. Super Key
4. Foreign Key
5. Composite Key
6. Alternate Key
7. Unique Key
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11. Primary Key
A primary key is a column of a table or
a set of columns that helps to identify
every record present in that table
uniquely. There can be only one
primary Key in a table.
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12. Database Languages
 Database languages, also known as query
languages or data query languages, are a
classification of programming languages
that developers use to define and access
databases, which are collections of
organized data that users can access
electronically.
 These languages allow users to complete
tasks such as controlling access to data,
defining and updating data and searching
for information within the database
management system (DBMS).
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13. Types of Database Languages
Introduction to Database
1. DATA
DEFINITION
LANGUAGE (DDL)
2. DATA
MANIPULATION
LANGUAGE (DML)
3. DATA CONTROL
LANGUAGE (DCL)
4. TRANSACTION
CONTROL
LANGUAGE (TCL)
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14. 1. Data
definition
language
(DDL)
Introduction to Database
CREATE: Creates a new database or
object, such as a table, index or column
ALTER: Changes the structure of the
database or object
DROP: Deletes the database or existing
objects
RENAME: Renames the database or
existing objects
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15. 2. Data
manipulation
language
(DML)
Introduction to Database
INSERT: Adds new data to the existing
database table
UPDATE: Changes or updates values in
the table
DELETE: Removes records or rows from
the table
SELECT: Retrieves data from the table or
multiple tables
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16. 3. Data control language (DCL)
Introduction to Database
GRANT: Gives a user access to the database
REVOKE: Removes a user's access to the database
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17. Purpose of database
software
 Data Redundancy or Data Duplication is
Minimized.
 Data Integrity is maintained in a Database
Management System.
 Data Consistency is also maintained in a
Database Management System.
 Backing up data from a single location is simple.
 In DBMSs, Data is housed in a secure central
location, and many access privileges can be
assigned to multiple people.
 One of the main benefits of a Database
Management System is that the same business
data can be made available to various personnel
at any time and from any location.
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18. Introduction to Database
Purpose of
database
software
 Database Management Systems also
ensures data durability, that is, even if there
is a power outage or any other disaster for
that matter, the data in the Database will
persist.
 Usage Of Query Languages
 Maintenance of a Large Database
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19. Is Excel Database
System?
Yes, Excel can store large amounts of
data in workbooks that contain one or
more worksheets. However, instead of
serving as a database management
system, such as Access, Excel is
optimized for data analysis and
calculation.
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20. Tip of the Day
Booting and Startup Stages
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