INSERT, UPDATE, and DELETE on Views

INSERT, UPDATE, and DELETE on views are supported as defined by SQL standards, under the following conditions:

• A view is updatable only if:

— It is defined to be a direct row and column subset of some base table, or a direct row and column subset of some other updatable view.

— The SQL of the view does not include DISTINCT, GROUP BY, or HAVING.

— The FROM clause of the view refers to exactly one table reference, and that table reference identifies either a base table or an updatable view.

• Derived columns are not updatable.

• A view with an aggregate expression in projection is not updatable whether GROUP BY is present or not.