2. WHAT IS DBMS?
Before answering this question. Let’s
learn the key Terminologies of DBMS.
3. DATA
Data is a Latin word meaning which is
plural in format and has “Datum” as its
singular format, layman may describe
data as “Raw facts and Figures”
0-9
A-Z
Special Characters etc.
4. INFORMATION
On processing raw facts and figures(DATA )
the outcome is in the form of meaningful
information.
Information is the key to “Decision Making”
7. DATABASE
Database is defined as the systematic
and organized information of data, for
effective and efficient retrieval and
modification of data as and when
required.
DATABASE
CENTRALIZED DISTRIBUTED
8. DATABASE
ADMINISTRATOR
Database Administrator is an expert or
team of experts who works as a
manager of the Database and is
responsible for:
Security
Data Backup
Data Recovery
Troubleshooting, etc.
10. DBMS
Database Management System is
collection of program schedules, that
allows one to store, fetch(retrieve),
modify or update data stored in
Database. One can create or drop
database using DBMS.Cthe popular
forms are:
Oracle, Sybase, MySQL, Microsoft SQL
Server
11. SCHEMA
Schema defines the structures of
Database, it is describe as the blueprint
of the database. We have three levels of
schema hat are classified on the basis
of different level of views available:
SCHEMA
INTERNAL SCHEMA
CONCEPTUAL SCHEMA
EXTERNAL SCHEMA
12. PRIMARY KEY
Primary Key – is used to recognized a
record uniquely. A primary key must be:
Unique – Value in primary column
cannot be repeated.
Not Null – The Primary Key cannot have
a null value i.e. The primary key cannot
be left blank.
13. FOREIGN KEY
Foreign Key - is the key is used to link
two functions in table(Table) in a
database.
In simple if we assume two tables Table
A and Table B, the primary key of Table
A will act as the foreign key in Table B.