The document discusses Edgar Frank "Ted" Codd, the inventor of the relational model for database management, and provides information on what a database is, why databases are needed, database abstraction levels, database architecture including two-tier and three-tier architectures. It defines a database as a collection of related files containing records, explains that databases make data easy to access and manage, and note that databases provide data security, integrity and concurrent access.

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2. Edgar F. Codd
Edgar Frank "Ted" Codd
(August 23, 1923 – April 18,
2003) was an English
computer scientist who,
while working for IBM,
invented the relational
model for database
management .
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3. What is a Data Base ?
Collection of related files containing records
of people,places,things,etc.
Data base makes Data easy to access and
manage .
A Database Management System (DBMS) is a
software package designed to store and
manage databases.
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4. Why do we need a Database ?
 A database is a place where you
can store information related to
a specific topic .
Data security and integrity .
Concurrent access, recovery .
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5. Three level Data Abstraction
View 1 View 2 ……...... View n
Logical
Level
Physical
Level
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6. Architecture
Client: The client are the user
machine which request for the
service to the server . It is also
called as front end .
Server: It is a machine which
provide service to the client . It is
also called as back end .
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7. Two tier Architecture
Application
User program are
Client present in
client machine
Application and database
are present at
server and both
Network
are connected
with interface
Database like JDBC and
System Server ODBC .
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8. Three Tier Architecture
User In three tier
Client architecture
Application communicati
Client on takes
Network
place from
client to
Application server and
Server
then
Server application to
Database
System database .
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