Please help me in getting this - I tried, but not working -
https://developer.salesforce.com/trailhead/data_security/data_security_fields

Every user record in our SFDC org has a User.Manager listed, except our CEO. SFDC won't allow a circular relationship, and every other user already reports to someone else, so SFDC won't let us list any other user as the CEO's manager (even, say, the CEO's assistant, or the VP of HR).

When using User.Manager to route approvals, this becomes a serious issue. We've implemented Expense Reports in SFDC, and use the Manager hierarchy for automatic routing. Finance is only triggered to pay approved expense reports. Therefore, we'd like the CEO's expense reports to route to our VP of Finance for approval.

We tried putting an inactive user in the CEO's User.Manager field, but it didn't work. When the CEO tries submitting an expense report for approval, SFDC complains that "This approval request requires the next approver to be determined by the Manager field. This value is empty. Please contact your administrator for more information." (Of course, the value isn't "empty," it's pointing to an inactive user.)

Any ideas for how to route approvals for the top of the manager hierarchy, i.e. our CEO?