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WITH CHECK OPTION
CREATE VIEW
Checks that the updated or inserted row satisfies the view definition. The row must be
selectable using the view. The WITH CHECK OPTION clause is only allowed on an updatable
view.
Notes • A view is deletable if deleting rows from that view is allowed. For a view to be deletable,
the view definition must satisfy the following conditions:
– The first FROM clause contains only one table reference or one view reference.
– There are no aggregate functions, DISTINCT clause, GROUP BY clause, or HAVING
clause in the view definition.
– If the first FROM clause contains a view reference, then the view referred to is
deletable.
• A view is updatable if updating rows from that view is allowed. For a view to be updatable,
the view has to satisfy the following conditions:
– The view is deletable (it satisfies all the previously specified conditions for
deletability).
– All the select expressions in the first SELECT clause of the view definition are simple
column references.
– If the first FROM clause contains a view reference, then the view referred to is
updatable.
• A view is insertable if inserting rows into that view is allowed. For a view to be insertable,
the view has to satisfy the following conditions:
– The view is updatable (it satisfies all the previously specified conditions for update
ability).
– If the first FROM clause contains a table reference, then all NOT NULL columns of the
table are selected in the first SELECT clause of the view definition.
– If the first FROM clause contains a view reference, then the view referred to is
insertable.
Example The following examples illustrate CREATE VIEW statements defined by query expressions:
CREATE VIEW ne_customers AS
SELECT name, address, city, state
FROM customer
WHERE state IN ( 'NH', 'MA', 'ME', 'RI', 'CT', 'VT' )
WITH CHECK OPTION ;
CREATE VIEW OrderCount (custnum, numorders) AS
SELECT CustNum, COUNT(*)
FROM Order
GROUP BY CustNum;
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