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What is RDBMS?

The term RDBMS stands for Relational Database Management System.
All new modern database management systems like SQL, MS SQL Server,IBM DB2, Oracle, MS-Access and My-SQL are based on RDBMS.
In RDBMS the term relational model was introduced by E.F. Codd.

History of RDBMS:

At 1970 to 1972, E.F. Codd published a paper to use relational database model.
RDBMS is generally based on the concept of E.F. Codd's relational model invention.

What is table ?

The table is collection of related data entries and contains rows and coloumn to store the data.The RDBMS use the tables to store the data.

1 Akshay 26 Cordinator
2 Shekhar 27 HR
3 Manpreet 26 Sales head
4 Vishal 34 Manager
5 Alok 22 Writer

What is row or record

A row is a part of table and it is called record.It conntain a specific entry in the table.This is horizontal entry in the table.

1 Akshay 26 Cordinator

What is column:

A column is a vertical entity in the table that contains all specific information in a field of a table. For example E_PROFILE in above table which contains all information regarding all employee in profile.

Sales Head

What is field:

Field is small entity in a table which consists information about every record in a table.In the above example employee table contain e_id,e_name,e_age and e_profile.

Null Values:

Null values in a table defines that the field has been left blank during the record insertion or creation. It is very different from the value that filled with zero or a field of Space.