View in SQL Server

Introduction

In this article, I describe Views in SQL Server. This is a simple topic. I hope this article will help you just like my Windows Store articles. Please give me your valuable suggestions and feedback to improve my articles.

 

What is a View

 

Views are database objects which are like virtual tables that have no physical storage and contains data from one table or multiple tables. A View does not have any physical storage so they do not contain any data. When we update, insert or apply any operation over the View then these operations are applied to the table(s) on which the view was created.

 

Types Of View

1. System View
2. User Define View

User Defined Views are important so I describe only User Defined Views. They are of two types:

1. Simple View
2. Complex view

Simple View

When a View is created on a single Table than it is called a Simple View. We can apply all operations on a Simple View that we can apply on a table.

 

First of all we create a table on which we create a view.

create table emp(empId int,empName varchar(15),empAdd varchar(15))

Now insert data by the following code. 

insert into emp
select 1,'deepak','UA'union all
select 2,'Middha','Punjab'union all
select 3,'d','Delhi'union all
select 4,'gourav','Noida'union all
select 5,'deepakia','Laksar'union all
select 6,'Deep','Haridwar'

Table 

Creation of a simple view

create view v1
as
select * from emp

Operation on view

See all the data of the view

select * from v1

See the specific data of the view

select * from v1 where empId=4

Insertion

insert into v1 values(7,'raj','canada');

 

Updating 

update v1 set empAdd='usa'where empId=7

Deletion

delete from v1 where empId=7

Renaming 

exec sp_rename 'v1','v11'

Logic of the View

exec sp_helptext v1

Dropping the View

drop view v1

Encrypted View

create view v1
with encryption
as
select * from emp

Complex view

Views created on more than one table are called Complex View. We cannot perform all operations of a table on a Complex View.

First of all we create a table and insert some data 

create table empStatus(empId int,empStatus varchar(10))

insert into empStatus
select 1,'active'union all
select 2,'inactive'union all
select 4,'active'union all
select 5,'inactive'union all
select 6,'active'

Table

select * from empStatus

  

Creation of complex view 

create View VComplex
as
select e.empId,e.empName,e1.empStatus from emp e inner join empStatus e1 on e.empId=e1.empId

See all the records

select * from VComplex

See specific record 

select * from VComplex where empId=4

If we try insert, update or delete in a complex view then it shows an error as in the following

insert into vcomplex values(11,'d','inactive')

Encryption of the Complex View

create View VComplex
With encryption
as
select e.empId,e.empName,e1.empStatus from emp e inner join empStatus e1 on e.empId=e1.empId

Summary

 

In this app I described Views in SQL Server. I hope this article has helped you to understand this topic. Please share if you know more about this. Your feedback and constructive contributions are welcome.