Updates on Views
Only a limited set of updates on views is supported because of problems that can occur. Updates are not supported on views that have more than one base table, or on any column whose source is not a simple column name (for example, set functions or computations).
Updating is supported only if it can be guaranteed (without looking at the actual data) that the result of updating the view is identical to that of updating the corresponding base table.
Note: Updating, deleting, or inserting data in a table using views is not recommended. You can update, delete, or insert with SQL statements, but you must abide by the following rules, keeping in mind that an error occurs if you attempt an operation that is not permitted.