SQL Alter View

View is a virtual and imaginary table come out as result -set of an SQL
statement. A virtual table contains rows and columns, as same as real
table. In SQL Alter View is used to modify a previous created view. The
advantage of Alter View hardly any effect on dependent procedure, trigger
and change permissions.
Understand with Example
The Tutorial illustrates an example from SQL Alter View. In this
Tutorial, we want to describe you how to alter a created view. For,
this we create a table 'Stu_Table' using create statement. The insert
into add the records or rows to the created table'Stu_Table'.The select
statemet return you all the record added by the insert into
statement.
Create Table Stu_Table
create table Stu_Table(Stu_Id integer(2), Stu_Name varchar(15), Stu_Class varchar(10))
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Insert data into Stu_Table
insert into Stu_Table values(1,'Komal',10);
insert into Stu_Table values(2,'Ajay',10);
insert into Stu_Table values(3,'Rakesh',10);
insert into Stu_Table values(4,'Bhanu',10);
insert into Stu_Table values(5,'Santosh',10);
insert into Stu_Table values(6,'Tanuj',10);
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Stu_Table
| Stu_Id |
Stu_Name |
Stu_Class |
| 1 |
Komal |
10 |
| 2 |
Ajay |
10 |
| 3 |
Rakesh |
10 |
| 4 |
Bhanu |
10 |
| 5 |
Santosh |
10 |
| 6 |
Tanuj |
10 |
Create View
Now we create a view of table 'Stu_Table'. The
view "Stu_View" lists all the field from the "Stu_View"
table. The view can be created with the help of given SQL Query.
CREATE VIEW Stu_View( Stu_id, Stu_Name, Stu_Class)
AS SELECT Stu_id, Stu_name, Stu_class
FROM Stu_Table
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View Stu_View
You can see the created view "Stu_View"
using View Stu_View statement.
| Stu_Id |
Stu_Name |
Stu_Class |
| 1 |
Komal |
10 |
| 2 |
Ajay |
10 |
| 3 |
Rakesh |
10 |
| 4 |
Bhanu |
10 |
| 5 |
Santosh |
10 |
| 6 |
Tanuj |
10 |
Alter View
The Alter View modify the existing created view
Stu_View. The ALTER VIEW statement is used to modify the
Stu_View enlisted all the list of field selected in select query. The WHERE
clause restrict the select query and return you the record based upon
condition whose stu_Id is less than equal to'5'.
ALTER VIEW Stu_View(Stu_id,Stu_Name,Stu_Class)
AS SELECT stu_id, stu_name, stu_class
FROM Stu_Table where Stu_Id <=5
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View Stu_View
| Stu_Id |
Stu_Name |
Stu_Class |
| 1 |
Komal |
10 |
| 2 |
Ajay |
10 |
| 3 |
Rakesh |
10 |
| 4 |
Bhanu |
10 |
| 5 |
Santosh |
10 |

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