RDBMS

 

  Basics of RDBMS & DBMS.

 

 

 

1) What is RDBMS?

RDBMS stands for “Relational Database Management System”.

RDBMS data is structured in database tables, fields and records.

Each RDBMS table consists of database table rows. Each database table row consists of one or more     database table fields. 
                RDBMS store the data into collection of tables, which might be related by common fields. RDBMS also provide relational operators to manipulate the data stored into the database tables.

Most RDBMS use SQL as database query language.

“In simple word:   RDBMS is the concept or procedure to store the data”  J  

2) What is DBMS?

“A collection of programs that enables you to store, modify, and extract information from  database”.

There are many different types of DBMS, ranging from small systems that run on personal       computers to huge systems that run on mainframes.

The following are examples of database applications:

·         automated teller machines

·         flight reservation systems

·         computerized parts inventory systems

·         computerized library systems

In Simple word: “DBMS is the software or Instance or Tool to access        RDBMS concepts”.

                 “Edgar Codd” introduced the relational database model.

Many modern DBMS do not conform to the Codd’s definition of a RDBMS, but nonetheless
 they are still considered to be RDBMS.

As SQL Professional we should have Knowledge of CODD’s Rule:

There are 12 Codd’s rules (actually there are 13 rule, starts from Zero (0) to 12 so, known as Codd’s 12 Rule).

0 Rule: System Qualify

1. The information rule

2. The guaranteed access rule

3. Systematic treatment of null values

4. Active online catalog based on the relational model

5. The comprehensive data sublanguage rule

6. The view updating rule

7. High-level insert, update, and delete

8. Physical data independence

9. Logical data independence

10. Integrity independence

11. Distribution independence

12. The non subversion rule

(Click Here to Read MORE about Codd's Rule)

2)
What is DBMS?