Difference between a view and a base relation: -

Views:
1. This is one type of relation which is not a part of the physical
database.
2. It has no direct or physical relation with the database.
3. Views can be used to provide security mechanism.
4. Modification through a view (e.g. insert update delete) generally
not permitted

Base Relation:
1. A base relation is a relation that is not a derived relation.
2. While it can manipulate the conceptual or physical relations stored
in the data.
3. It does not provide security.
4. Modification may be done with a base relation.

We can assign the view a name & relate it the query expression as
Create View <View Name> as <Query Expression>
Let EMPLOYEE be the relation. We create the table EMPLOYEE as follows:-

Create table EMPLOYEE
(Emp_No integer of null
Name char (20)
Skill chars (20)
Sal_Rate decimal (10 2)
DOB date
Address char (100) )
For a very personal or confidential matter every user is not
permitted to see the Sal_Rate of an EMPLOYEE. For such users DBA can
create a view for example EMP_VIEW defined as:-

Create view EMP_VIEW as
(Select Emp_No Name Skill DOB Address
From EMPLOYEE)

A VIEW is only a mirror image of table which is used at places where

large access to a table is required.

Views cannot be updated deleted and modified but we could select data

from views easily.

Table - Storage Unit Contain Rows and Columns

View - Logical Subset of Tables

View

View is an Database Object we can use DML it affects the base table and view.we can create a object for that table.

Table

we cant use that to be a object It use for store the data only and manipulate the data.

Table : Relational Database is composed of tables that contain related data.

View :

1. Views are created from one or more than one table by joins with selected columns.

2. Views acts as a layer between user and table.

3. Views are created to hide some columns from the user for security reasons and to hide information exist in the column.

4. Views reduces the effort for writing queries to access specific columns every time.

5. Reports can be created on views.

6. View doesn't contain any data.

For data hiding to users from the data table we use views. Views stores only a particular query.Whenever we call that view it executes that query only. It does not store any data.We can also get some attributes of a table as view.

View is different perspective to see output from a table.

View data can not take part in Manipulation.

We can update or delete view.

View is nothing but a query file which stores the Sql Query which is similar to the query file in Foxpro. When executed the query returns the rows from the tables specified in the query which satisfies the conditions (to a dynamic virtual table which has the column names specified in the query). That is why each an every time the view displays different result set depending on the data in the table.