DB2 - Views


This chapter describes introduction of views, creating, modifying and dropping the views.

Introduction

A view is an alternative way of representing the data stored in the tables. It is not an actual table and it does not have any permanent storage. View provides a way of looking at the data in one or more tables. It is a named specification of a result table.

Creating a view

You can create a view using the following syntax:

Syntax:

db2 create view <view_name> (<col_name>,
<col_name1...) as select <cols>.. 
from <table_name> 

Example: Creating view for shopper.sales1 table

db2 create view view_sales1(id, itemname, qty, price) 
as select id, itemname, qty, price from 
shopper.sales1  

Modifying a view

You can modify a view using the following syntax:

Syntax:

db2 alter view <view_name> alter <col_name> 
add scope <table_or_view_name> 

Example: [To add new table column to existing view ‘view_sales1’]

db2 alter view view_sales1 alter id add 
scope shopper.sales1  

Dropping the view

You can drop a view using the following syntax:

Syntax:

db2 drop view <view_name> 

Example:

db2 drop view sales1_view  
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