In this article we move on to (separately licensed) “OLTP” compression (originally known as “compress for all operations”).
We will re-run some of our tests to see how differently Oracle can behave with this option in play.
To learn whether and in what ways the columns of an inherently updatable view can be modified, query the USER_UPDATABLE_COLUMNS data dictionary view.
The information displayed by this view is meaningful only for inherently updatable views.
Therefore, you should not write triggers intended to affect the content of the materialized view. In other words, the database fires the triggers instead of performing DML on the view.