1 – CASCADE
Deletes the routine definition even when there are dependencies on the specified routine. Any referencing routines are marked invalid.
2 – IF_EXISTS
Prevents SQL command language from displaying error messages if the referenced object does not exist in the database.
3 – RESTRICT
Prevents the removal of an external or stored routine definition when the routine is referenced by any other object within an Oracle Rdb database. RESTRICT is the default.
4 – routine-name
Identifies the name of the external or stored routine definition in the Oracle Rdb database.