How to fix the Oracle error ORA-22894: cannot add constraint on existing unscoped REF columns of non-empty tables?

In this post, you’ll learn more about the Oracle ErrorORA-22894: cannot add constraint on existing unscoped REF columns of non-empty tables with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-22894: cannot add constraint on existing unscoped REF columns of non-empty tables

Reason for the Error ORA-22894: cannot add constraint on existing unscoped REF columns of non-empty tables

An attempt was made to add a constraint to existing unscoped REF columns of a table which contains one or more rows.

How to fix the Error ORA-22894: cannot add constraint on existing unscoped REF columns of non-empty tables ?

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

Remove the constraint specification or add the constraint after emptying the table.