diff --git a/confskel/openldap/ldif/olcDatabase.ldif b/confskel/openldap/ldif/olcDatabase.ldif
index b9b68ec..12ee550 100644
--- a/confskel/openldap/ldif/olcDatabase.ldif
+++ b/confskel/openldap/ldif/olcDatabase.ldif
@@ -40,7 +40,7 @@ olcDbIndex: objectClass eq
 olcDbIndex: krb5PrincipalName eq,pres
 olcDbIndex: cn eq,pres,subinitial
 olcDbIndex: mail eq,pres
-olcDbIndex: uid pres,eq
+olcDbIndex: uid pres,eq,sub
 olcDbIndex: uidNumber eq
 olcDbIndex: gidNumber eq
 olcDbLinearIndex: FALSE