How to fix the Oracle error ORA-29657: class defined in EXTERNAL NAME clause is used in another subtype?

In this post, you’ll learn more about the Oracle ErrorORA-29657: class defined in EXTERNAL NAME clause is used in another subtype with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-29657: class defined in EXTERNAL NAME clause is used in another subtype

Reason for the Error ORA-29657: class defined in EXTERNAL NAME clause is used in another subtype

The supertype has an existing type that has the same value for the EXTERNAL NAME.

How to fix the Error ORA-29657: class defined in EXTERNAL NAME clause is used in another subtype ?

You can fix this error in Oracle by following the below steps

Make sure the EXTERNAL NAME clause is unique among subtypes.