Unless an INSTEAD OF trigger is created on the view. Updating Views with JoinsĪ view that contains a join will only be updateable on one side of the join, Project or an Access database with a form bound to a view that contains WITHĬHECK OPTION would allow you to automatically have the criteria enforcedįor new or updated records. Of a form limits the records that are displayed in the form when you open it,īut it doesn't limit what records can be added in the form. You may have noticed in Access that placing criteria on the RecordSource query Statement would succeed, and a requery of the view would return no rows. If you did not have WITH CHECK OPTION defined, the UPDATE The following Transact-SQL statement attempting to update data by moving everyoneįrom Paris to Lyons will fail because Lyons does not meet the criteria defined SELECT CompanyName, ContactName, Phone, City Listing 9.12 Creating a View Using WITH CHECK OPTION CREATE VIEW vwCustomersParis Showing customers from Paris using the WITH CHECK OPTION statement. In a way that causes them to vanish from the view. The WITH CHECK OPTION clause forces all data-modification statementsĮxecuted against the view to adhere to the criteria set within the WHEREĬlause of the SELECT statement defining the view. For example, if the view selectsĪll customers who live in Paris, and data is modified to either add or editĪ row that does not have City = 'Paris', the data willīe modified in the base table but not shown in the view, unless WITHĬHECK OPTION is used when defining the view. Text and image columns can't be modified through views. Statements were being executed directly against the base table. YouĬan't modify data in views that use GROUP BY or DISTINCTĪll columns being modified are subject to the same restrictions as if the You can't directly modify data in views based on union queries. If the view contains joins between multiple tables, you can only insertĪnd update one table in the view, and you can't delete rows. You can insert, update, and delete rows in a view, subject to the following Restrictions on Updating Data Through Views Views cannot be used asĪ mechanism to override any constraints, rules, or referential integrity defined Modification always takes place at the table level. A view can be used in a query that updates data, subject to a few restrictions.īear in mind that a view is not a table and contains no datathe actual
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