How to fix the Oracle error ORA-37187: null parent and child pair found in parent-child hierarchy?

In this post, you’ll learn more about the Oracle ErrorORA-37187: null parent and child pair found in parent-child hierarchy with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-37187: null parent and child pair found in parent-child hierarchy

Reason for the Error ORA-37187: null parent and child pair found in parent-child hierarchy

While reading values for a parent-child hierarchy, a row was retrieved which had both null child and parent values.

How to fix the Error ORA-37187: null parent and child pair found in parent-child hierarchy ?

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

Correct the source table or SQL to return value parent and child pairs.