5. Relational Database Management System
RDBMS:
• A RDBMS is a collection of
software programs for
creating, maintaining,
modifying and manipulating
a relationship.
DBMS:
• A DBMS is a collection of
programs that are used
to create and maintain a
database.
A Relational Database
Management System
(RDBMS) is a DBMS that is
based on the relational
model.
11. Relational Data Integrity
Data Integrity means reliability and
accuracy of data. DBMS provides several
mechanism to enforce integrity of the
data in a column.
Data integrity falls into following
categories:
Entity Integrity
Domain Integrity
Referential Integrity
12. CONTIUNE…
Entity Integrity
Entity integrity means it should be easy to
identify each entity in the database.
An entity is any thing like an object, subject or
event represented in the database.
Domain Integrity
A set of values that can be stored in a column is
called a DOMAIN.
Domain Integrity enforces restriction on the
values entered in a column.
It specify the validity of a specific data entry in a
column.
13. CONTINUE…
REFERENTIAL INTEGRITY
referential integrity preserves the defined
relationship between tables when records are
added or deleted.
It ensures that key values are consistent
across the table.
14. REFERENTIAL INTEGRITY
MASTER TABLE
Reg. No. Name class
2013-ag-1411 Amer Palwasha BS
2013-ag-2301 Abdul Rafy BS
2011-ag-6988 Ameer Hamza MS
CHILD TABLE
Reg. No. Subjects Marks
2013-ag-1411 DBMS 82
2013-ag-1411 OOP 77
2013-ag-2301 DBMS 91
2013-ag-2301 OOP 88
2011-ag-6988 DBMS 78
201-ag-6988 OOP 80
15. DATABASE LANGUAGES
Data Definition Language (DDL)
Data Manipulation Language (DML)
These languages are called data sub-languages.
Many DBMSs provide the facility to embed the
sub-language in a high level programming
Language like C++, Java and Visual Basic etc.
In this situation, the high level language is called
HOST language.
16. DDL
Data Definition Language (DDL) statements are used
to define the database structure or schema.
Some examples:
• CREATE - to create objects in the database
• ALTER - alters the structure of the database
• DROP - delete objects from the database
• TRUNCATE - remove all records from a table
including all spaces allocated for the records are
removed
• COMMENT - add comments to the data dictionary
• RENAME - rename an object
17. DML
Data Manipulation Language (DML) statements are
used for managing data within schema objects.
Some examples:
• SELECT - retrieve data from the a database
• INSERT - insert data into a table
• UPDATE - updates existing data within a table
• DELETE - deletes all records from a table, the space
for the records remain
• MERGE - UPSERT operation (insert or update)
• CALL - call a PL/SQL or Java subprogram
• EXPLAIN PLAN - explain access path to data
• LOCK TABLE - control concurrency
18. PROPERTIES
Atomic Values in Fields
Entries From Same Domain
Unique Tuples
Unique Attribute Name
Insignificant Attribute
Sequence
Insignificant Tuple Sequence
19. ADVANTAGES OF RDBMS
Increases the sharing of data and faster
development of new applications
Support a simple data structure, namely tables or
relations
Limit redundancy or replication of data
Provide physical data independence so users do not
have to be aware of underlying objects
Expandability is relatively easy to achieve by adding
new views of the data as they are required.
Better backup and recovery procedures
Solves many problems created by other data models
The ability to handle efficiently simple data types
Multiple users can access which is not possible
20. DISADVANTAGES OF RDBMS
Software is complex
Complex software means expensive
hardware
Requires skilled knowledge to implement
Certain applications are slower processing
More difficult to recover if data is lost
Difficult to represent complex data types
22. Edgar Frank Ted Codd
E.F.Codd was an English
Computer scientist who while
working for IBM,
Invented the
relational model
for DBMS.
23. Codd’s Rule
Rule 1: The Information Rule
Rule 2: the Guaranteed Access Rule
Rule 3: Systematic Treatment of NULL values
Rule 4: Active online catalog Base don the
Relational Model
Rule 5: Comprehensive Data Sub-language
Rule
Rule 6: View Updating Rule
24. CONTINUE…
Rule 7: High Level Insert, Update and
Delete
Rule 8: Physical Data Independence Rule
RULE 9:Logical Data Independence Rule
Rule 10: Integrity Independence Rule
Rule 11: Distribution Independence Rule
Non-Subversion Rule