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Relational Data Base Manangement System

DBMS:
Ø  DBMS stands for Data base management system.
Ø  DBMS is a set of programs in an operating system that creates and maintains a database.
Ø  Allow user to store and restive data from database.


(Data base management system)
RDBMS:
Ø  RDBMS stands for Relational for Data base management system.
Ø  In Relational data base management system everything is maintained in table format.
Ø  Now a day’s relational database management system is most powerful.
Ø  In Relational database management system maintains relationship between among the tables.
Ø  Relational database management system is developed by Dr.E.F Codd in 1970.


Ø  In picture demonstrates about a relational model. In relational database management system every data is stores in table.
Ø  A table is combination of rows and columns.
Ø  In relational database management system each Row is called as Tuple.
Ø  In relational database management system each Column is called as Attributes.
Ø  Every database is divided into number of tables and they are connected through the “Key Fields“.
Ø  Data is in the form of a table. In table data is stored in form of rows and columns.
Ø  “Key Fields“ are nothing but columns in a table.

Difference between DBMS and RDBMS:
Now a day’s RDBMS is Replaces the DBMS because.

 DMBS:
  • In data base management system Data is stored in single table.
  • If you want to update record in a table you need to update an entire database.
  • It is very time processing.
  • No relationships between among the tables in data base management system.

Student_ID
Student Name
Address
Phone number
Maths
DBMS
1001
Rakesh
Khammam
123456
78
87
1002
Dave
USA
654123
88
98


  
RDBMS:
  • In Relational data base management system Data is stored in multiple tables among with relationship using “Key Fields”.
  • If you want to update record in a table you need to update an single table only.
  • Comparing to DBMS RDBMS is Very fast.
  • Relationships exists in  between among the tables in Relational  data base management system.
(Student Personal Table)

Student_ID
Student Name
Address
Phone number
1001
Rakesh
Khammam
123456
1002
Dave
USA
654123
(Marks Table)
Student_ID
  Maths
DBMS
1001
78
87
1002
88
98

In above Student Personal table and Marks table there is conman column is "Student_ID" is  called "Key Filed". if you want update the marks of the student you need to update only single table only.
Key Points RDBMS:
·         RDBMS stands for Relational database management system.
·         The model was developed by in IBM research scientist and mathematician Dr.E.F Codd in 1970.
·         Provides facility Primary key, unique identify rows in table.
·         RDBMS is most widely used in data model.
·         Majority of current database used relational database management system.        
·         In Relational data base management system data is stored in tables.
·         Tables are combination of Rows and Columns.
·         Rows are known as tuples.
·         Columns are known as attributes.
·         Each row in a table fixed number of attributes.
·         It reduces the data redundancy and data integrity with in database system.
·         Redundancy means avoid duplication of data.
·         Integrity means valid  data is stored in tables (By using constraints)  


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