For example, consider a directory information tree (DIT) where users have a manager attribute with a value of the DN of the employee as follows.

dn: uid=apeters,ou=people,dc=example,dc=com 
objectClass: person 
objectClass: inetOrgPerson 
objectClass: organizationalPerson 
objectClass: top 
manager:uid=jdoe,ou=people,dc=example,dc=com 
uid: apeters
... (more attributes) ...

You can set up a mirror virtual attribute so that the returned value for the managerName virtual attribute can be the cn value of the entry referenced by the manager attribute.

$ bin/ldapsearch --baseDN dc=example,dc=com "(uid=apeters)" \ 
dn: uid=apeters,ou=people,dc=example,dc=com

objectClass: person 
objectClass: inetOrgPerson 
objectClass: organizationalPerson 
objectClass: top 
manager:uid=jdoe,ou=people,dc=example,dc=com 
managerName: John Doe 
uid: apeters
... (more attributes not shown) ...