Identity in SQL

What is Identity in Sql:



An identity column of a table is a column whose value increases automatically. The value in an identity column is crated by the server. A user generally cannot insert a value into an identity column.


Example:

1. CREATE TABLE EMPLOYEE  
2. (  
3.    IID INT IDENTITY(1,1),  
4.    NAME [varchar](MAX) NOT NULL,  
5.    AGE INT NOT NULL  
6. )  

IDENTITY_INSERT ON allows a user to insert data into an Identity column and IDENTITY_INSERT OFF restricts a user from inserting data into an Identity column.