1. INFORMATION MANAGEMENT
CC105 (Lecture/Lab)
(IT) (BAIT-2A) | PROF. (Mrs. Fanny) | SEM 1 2022
1
History of Database
● The concept of a database existed
long before computers.
● Data was stored in journals, in
libraries, and in hundreds of filing
cabinets.
● Everything was recorded via paper
and that meant it took up space,
was hard to find, and difficult to
back up.
● 1960 - Charles Bachman designed
the first computerized database
● 1970 - E. F. Codd released his
paper “A Relational Model of Data
for Large Shared Data Banks”.
● 1980 - Growth and
Standardization. SQL(Structured
Query Language) has become the
standard language used for
databases.
File Systems
● It is used by a manager of any
small organization to track
necessary data.
Disadvantage of a File Systems
● Program-data dependence
● Duplication of Data
● Limited Data Sharing
● Lengthy Development Times
● Excessive Program Maintenance
Database System
● Has 5 major parts of a database
system
● Hardware
● Software
○ Operating Systems
Software
○ DBMS Software
● People
○ Systems Administrators
○ Database Administrators
○ Database Designers
○ Systems Analysts and
Programmers
○ End users
● Procedures
● Data
Database
● A shared collection of related data
used to support the activities of a
particular organization.
● It can be viewed as a repository of
data that is defined once and then
accessed by various users.
Properties of Database
● It is a representation of some
aspect of the real world or a
collection
of data elements (facts)
representing real-world
information.
● A database is logical, coherent and
internally consistent.
● A database is designed, built and
populated with data for a specific
purpose.
● Each data item is stored in a field.
● A combination of fields makes up a
table.
Database Management System
● Stores data in such a way that it
becomes easier to retrieve,
manipulate, and produce
information.
Characteristics of DBMS
● Real-world Entity
● Relation-based Tables
● Isolation Of Data And Application
● Less Redundancy
● Consistency
● Query Language
2. INFORMATION MANAGEMENT
CC105 (Lecture/Lab)
(IT) (BAIT-2A) | PROF. (Mrs. Fanny) | SEM 1 2022
2
● ACID Properties
● Multi-user And Concurrent Access
● Multiple Views
● Security
DBMS Users
● End users
● Administrators
● Designers
Information Management
● used to collect, manage, preserve,
store and deliver information.
● The guiding principles that allow
information to be available to the
right people at the right time.
● The view that all information, both
digital and physical, is an asset
that requires proper management.
● The organizational and social
contexts in which information
exists.
● Is an umbrella term that
encompasses all the systems and
processes within an organization
for the creation and use of
corporate information.
● More than just technology.
● about the business processes and
practices that underpin the
creation and use of information.
● It is also about the information
itself, including the structure of
information (“information
architecture”), metadata, content
quality, and more.
Purpose of Information Management
● To Design, develop, manage, and
use information with insight and
innovation.
● To Support decision making and
create value for individuals,
organizations, communities, and
societies.
Database Structure
● collection of interrelated tables
eg. studied subjects grade.
Table/Entity
● collection of row instances
eg.
TSTUDREC
studid name age course
123 fanny 18 BSCS
234 airel 17 BSIT
345 me 18 BSCS
Row/Record/Tuple
● collection of field
● row instance
eg.
studid name age course
123 fanny 18 BSCS
Field/Column/Attribute
● this is where the data is stored
● smallest unit in a DB
eg.
studid name age course
DBMS ARCHITECTURE
● will help us understand the
components of database system
and the relation among them.
Types of DBMS Architecture
● Single tier architecture - the
simplest architecture of
Database in which the client,
server, and Database all reside
on the same machine
● Two tier architecture - the
presentation layer runs on a client
3. INFORMATION MANAGEMENT
CC105 (Lecture/Lab)
(IT) (BAIT-2A) | PROF. (Mrs. Fanny) | SEM 1 2022
3
(PC, Mobile, Tablet, etc.), and data
is stored on a server called the
second tier. Two tier architecture
provides added security to the
DBMS as it is not exposed to the
end-user directly. It also provides
direct and faster communication.
● Three tier architecture - the most
popular client server architecture in
DBMS in which the development
and maintenance of functional
processes, logic, data access, data
storage, and user interface is done
independently as separate
modules. Three Tier architecture
contains a presentation layer, an
application layer, and a database
server.
DBMS - 3 LEVEL ARCHITECTURE
● External level - It is also called
view level. The reason this level is
called “view” is because several
users can view their desired data
from this level which is internally
fetched from the database with the
help of conceptual and internal
level mapping. External level is the
“top level” of the Three Level
DBMS Architecture.
● Conceptual level - It is also called
logical level. The whole design of
the database such as relationship
among data, schema of data etc.
are described in this level.
● Internal level - This level is also
known as physical level. This level
describes how the data is actually
stored in the storage devices. This
level is also responsible for
allocating space to the data. This
is the lowest level of the
architecture.
DATA ABSTRACTION
● Physical level - This is the lowest
level of data abstraction. It tells us
how the data is actually stored in
memory.
● Logical level - This level comprises
the information that is actually
stored in the database in the form
of tables. It also stores the
relationship among the data
entities in relatively simple
structures.
● View level - This is the highest
level of abstraction. Only a part of
the actual database is viewed by
the users. This level exists to ease
the accessibility of the database by
an individual user. Users view data
in the form of rows and columns.
Tables and relations are used to
store data. Multiple views of the
same database may exist. Users
can just view the data and interact
with the database, storage and
implementation details are hidden
from them.
SCHEMA
● Design of a database is called the
schema.
● A schema contains schema
objects like table, foreign key,
primary key, views, columns, data
types, stored procedure, etc.
● Schema is of three types: Physical
schema, logical schema and view
schema.
INSTANCES
● Data stored in database at a
particular moment of time
● It contains a snapshot of the
database.
4. INFORMATION MANAGEMENT
CC105 (Lecture/Lab)
(IT) (BAIT-2A) | PROF. (Mrs. Fanny) | SEM 1 2022
4
● A DBMS ensures that its every
instance (state) is in a valid state,
by diligently following all the
validations, constraints, and
conditions that the database
designers have imposed.
DATA MODELS
● A modeling of the data description,
data semantics, and consistency
constraints of the data.
● It provides the conceptual tools for
describing the design of a
database at each level of data
abstraction.
DATA INDEPENDENCE
● The capacity to change the
schema at one level of a database
system without having changed
the schema at the next higher
level.
2 TYPES OF DATA INDEPENDENCE
● Logical Data Independence - is
defined as the ability to make
changes in the structure of the
middle level of the Database
Management System (DBMS)
without affecting the highest-level
schema or application programs.
● Physical Data Independence -
defined as the ability to make
changes in the structure of the
lowest level of the Database
Management System (DBMS)
without affecting the higher-level
schemas.
DBMS LANGUAGES
● A DBMS has appropriate
languages and interfaces to
express database queries and
updates.
● Database languages can be used
to read, store and update the data
in the database.
DATA DEFINITION LANGUAGE (DDL)
● Create: It is used to create objects
in the database.
● Alter: It is used to alter the
structure of the database.
● Drop: It is used to delete objects
from the database.
● Truncate: It is used to remove all
records from a table.
● Rename: It is used to rename an
object.
● Comment: It is used to comment
on the data dictionary.
DATA MANIPULATION LANGUAGE
(DML)
● Select: It is used to retrieve data
from a database.
● Insert: It is used to insert data into
a table.
● Update: It is used to update
existing data within a table.
● Delete: It is used to delete all
records from a table.
DATA CONTROL LANGUAGE (DCL)
● Grant: It is used to give user
access privileges to a database.
● Revoke: It is used to take back
permissions from the user.
IMPORTANT INFO
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