In SQL, use the CREATE VIEW statement to create a view. The syntax is: Named view: The view name is followed by AS to define the subquery: The AS keyword is followed by the subquery specified as the basis of the view
Commands to create views in SQL
In SQL, you can use the CREATE VIEW
statement to create a view.
Syntax
##CREATE VIEW View name
AS Subquery
Steps
- Named view: Use viewname
to specify the name of the view to be created.
- Define a subquery: Specify the subquery to be the basis of the view after the AS
keyword. Subqueries can contain SELECT statements as well as other SQL operations.
Example
The following statement creates a view namedcustomer_view that contains the customer names and addresses in the customers table:
CREATE VIEW customer_view AS SELECT customer_name, address FROM customers;
Note
- The view is just a virtualization of the underlying table data and does not store actual data.
- Views can reference other views or tables.
- Changing the data in the underlying table will also affect the data in the view.
- Views can be used to improve performance because they can precompute the results of common queries.
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