How to fix the Oracle error ORA-37186: null child value for parent (string) found in parent-child hierarchy?

In this post, you’ll learn more about the Oracle ErrorORA-37186: null child value for parent (string) 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-37186: null child value for parent (string) found in parent-child hierarchy

Reason for the Error ORA-37186: null child value for parent (string) found in parent-child hierarchy

While reading values for a parent-child hierarchy, a NULL child value was found for a non-NULL parent

How to fix the Error ORA-37186: null child value for parent (string) 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.