Oracle Error PLS-00648: type of supertype attribute “string” can not be a subtype or reference to a subtype in this release

Oracle Error Message

PLS-00648: type of supertype attribute “string” can not be a subtype or reference to a subtype in this release

Reason for the Error

User tried to complete a type, Tsub as a subtype of another type, Tsuper where Tsuper contained an attribute of type Tsub or of type REF to Tsub. This is an implementation restriction.

Solution

Change the design of code to not use any type with attribute whose type is of subtype or REF to subtype.