How to fix the Oracle error ORA-39271: Cannot alter substitutability of column: string?

In this post, you’ll learn more about the Oracle ErrorORA-39271: Cannot alter substitutability of column: string with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-39271: Cannot alter substitutability of column: string

Reason for the Error ORA-39271: Cannot alter substitutability of column: string

DBMS_METADATA_DIFF was comparing two table columns. This error may occur because the first column is substitutable and the second column is not, or because the first column is OF TYPE and the second column is substitutable.

How to fix the Error ORA-39271: Cannot alter substitutability of column: string ?

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

The difference cannot be eliminated with an SQL ALTER statement.