414 Part I EXAM PREPARATION GO DROP VIEW
414 Part I EXAM PREPARATION GO DROP VIEW auth1 GO SELECT * FROM auth2 GO When this code is executed, you get the following error message: Server: Msg 208, Level 16, State 1, Procedure auth2, Line 3 Invalid object name pubs.dbo.auth1 . Server: Msg 4413, Level 16, State 1, Line 1 Could not use view or function auth2 because of binding errors. This error message lets you know that the dependent view pubs.dbo.auth1 is not present in the database. MODIFYING DATA THROUGH VIEWS . Manage data manipulation by using views. Not only can you retrieve data by using a view, you can also modify the data. Modification includes all inserts, deletes, and updates. When you modify, delete, and update data, the data definition in the view does not change; the data modification is aimed at the underlying referenced tables associated with the view. A view does not in any way lose its definition; therefore it is not affected in any way when modification queries are executed. You can easily modify the data through a view, as long as the view has been based on at least one table, and it does not SELECT aggregate functions. In addition, if you need to perform additional data modification through the view, you can use the INSTEAD OF triggers. INSTEAD OF triggers exist for UPDATE, DELETE, and INSERT statements. For the time being, we ll stick with modifying data through a view without the help of the INSTEAD OF trigger, which is covered in greater detail in Chapter 8, Triggers. Inserting Rows Through Views In addition to retrieving rows, you can use views to insert data into an underlying base table. Adding data through a view is extremely
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