CREATE_VIEW (l)
Constructs a virtual table
SYNOPSIS
CREATE VIEW view AS SELECT query
view
The name of a view to be created.
query
An SQL query which will provide the columns and rows of the view.
Refer to the SELECT statement for more information
about valid arguments.
CREATE
The message returned if the view is successfully created.
ERROR: Relation 'view' already exists
This error occurs if the view specified already exists in the database.
NOTICE create: attribute named "column" has an unknown type
The view will be created having a column with an unknown type
if you do not specify it. For example, the following command gives
an error:
CREATE VIEW vista AS SELECT 'Hello World'
whereas this command does not:
CREATE VIEW vista AS SELECT 'Hello World'::text
DESCRIPTION
CREATE VIEW will define a view of a table or
class. This view is not physically materialized. Specifically, a query
rewrite retrieve rule is automatically generated to support
retrieve operations on views.
Currently, views are read only.
Use the DROP VIEW statement to drop views.
USAGE
CREATE VIEW kinds AS
SELECT *
FROM films
WHERE kind = 'Comedy';
SELECT * FROM kinds;
code |title |did| date_prod|kind |len
-----+-------------------------+---+----------+----------+------
UA502|Bananas |105|1971-07-13|Comedy | 01:22
C_701|There's a Girl in my Soup|107|1970-06-11|Comedy | 01:36
COMPATIBILITY
CREATE VIEW view [ column [, ...] ]
AS SELECT expression [ AS colname ] [, ...]
FROM table [ WHERE condition ]
[ WITH [ CASCADE | LOCAL ] CHECK OPTION ]
The optional clauses for the full SQL92 command are:
CHECK OPTION
This option is to do with updatable views.
All INSERTs and UPDATEs on the view will be
checked to ensure data satisfy the view-defining
condition. If they do not, the update will be rejected.
LOCAL
Check for integrity on this view.
CASCADE
Check for integrity on this view and on any dependent
view. CASCADE is assumed if neither CASCADE nor LOCAL is specified.
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