Updating tables through object views in oracle
This is a requirement of the relational model and is referred to as relational closure.
In fact, the evidence supports not using views in this manner.
For example, the UNION operator can not be used in a view and you cannot create a trigger on a view.
All of the basic DDL statements can be used to create and manage views including CREATE, DROP, and ALTER.
Therefore, a view can be considered a logical table. The SQL comprising the view is executed only when the view is accessed and views can be accessed by SQL in the same way that tables are by SQL.
No physical structure is required of a view; it is a representation of data that is stored in other tables. When modifying data through a view (that is, using INSERT or UPDATE statements) certain limitations exist depending upon the type of view.Furthermore, views are simple to create and implement.But unfortunately most users do not adhere to a systematic and logical approach to view creation.SCHEMA_AND_DATA is the default value for memory optimized tables.