Virtual Directory Information Tree Views78 Netscape Directory Server Deployment Guide • October 2004This view of the organization serves well in many cases, but having just this oneview can be very limiting for directory navigation and management. For example,an organization hierarchy is fine if you are looking for entries belonging to peoplein the Accounts department. However, this view is much less useful for findingentries that belong to people in a geographical location, say Mountain View,California. The second query is equally valid as the first one, yet it requiresknowledge of the attributes contained in the entries and additional search tools.For such a case, navigation via the DIT is not an option.In a similar vein, management of the directory is made very much easier byhaving a DIT that matches the requirements of the management function. Theorganization of your DIT may be affected by other factors, too, such as replicationand migration considerations, that cause the DIT to have functional utility forthose applications but very little practical utility in other cases.From the above discussion, it is clear that hierarchies are a useful mechanism fornavigation and management. Yet, to avoid the burden of making changes to anexisting DIT, a deployment may elect to forgo a hierarchy altogether in favor of aflat DIT.It would be advantageous for deployments if the directory provided a way tocreate an arbitrary number of hierarchies that get mapped to entries withouthaving to move the target entries in question. The virtual DIT views feature ofDirectory Server resolves the quandary of deciding the DIT type you should electfor your directory deployment.Introduction to Virtual DIT ViewsVirtual DIT views are a way to navigate hierarchically entries that do not requirethe physical existence of those entries in any particular place. The virtual DITview uses information about the entries to place them in the view hierarchy. Toclient applications, virtual DIT views look just like ordinary container hierarchies.In a sense, virtual DIT views superimpose a DIT hierarchy over a set of entries,irrespective of whether those entries are in a flat namespace or in anotherhierarchy of their own.Creating a virtual DIT view hierarchy is just like creating a normal DIT hierarchy.You create the same entries (for example, organizational unit entries) but with anadditional object class (nsview) and a filter attribute (nsviewfilter) thatdescribes the view. Once you add the additional attribute, the entries that matchthe view filter will instantly populate the view. Note that the target entries onlyappear to exist in the view; their true location never changes. Virtual DIT viewsact just like normal DITs in that a subtree or a one-level search can be performedwith the expected results being returned.
