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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