Oracle 9i A View-based constraint reputation

Starting with Oracle 9i, Oracle allows you to make a reputation for primary keys, unique keys, and foreign KEY constraints for view. The NOT NULL constraint can inherit from the base table, so it is not allowed to display the declaration.

Because the view constraint is just a declaration, its state can only be disable novalidate.

The following is a simple example description:

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This constraint is not actually binding because it is only a "constraint declaration":

Author: 51cto Blog Oracle Little Bastard