A view is something like a window into a table. It is a
logical structure that derives its data from other tables which can be tables
or other views. Views are normally used for making it easy for accessing
certain data and for hiding other pieces of data. A view does not store data,
rather it shows the data of the table. The command for creating a view on a
table is:
Listing 2
CREATE VIEW viewdemo AS
SELECT demo_id, demo_name, demo_address
FROM demo
WHERE demo_id >10;
Views can be built from simple queries that select only a
subset of a table or they can be built from join query operating on multiple
tables. But it is not possible to modifying a view after creating it, though it
can be replaced.