Thursday, December 31, 2009

SharePoint Taxonomy Hierarchy

If you’re wondering how to organize your SharePoint 2010 Enterprise Managed Metadata (EMM), you should start by reading the TechNet article, Plan terms and term sets (SharePoint Server 2010). I’m going to highlight some of the key points of that article and also add a few points from other sources.

While the TechNet article reminds us that you could simply allow your users to add keywords and then use their input to create your taxonomy—promoting keywords to managed terms—it seems likely that most organizations will want to start with an organized metadata hierarchy.

As explained in SharePoint Taxonomy Part One – Introduction to SharePoint Managed Metadata, the SharePoint 2010 EMM is organized into a hierarchy. The objects within this hierarchy are term stores, groups, term sets, and terms.

Keywords are stored in a non-hierarchical fashion in there own storage space.

These are the rules for the taxonomy hierarchy:
When a Managed Metadata service is created, a term store will be created. Once you have a term store, you can create a group. A group is a security boundary.
• Once you have a group, you can create a term set. A term set must be the child of a single parent group.
• Under a term set, terms can be created. A term can be the child of a term set, or of another term.
• A term can be added as a child of another term.
• Terms can be nested to seven levels. [Update: this documented rule is not enforced in the RTM version]

One of the key points of the TechNet article about planning your terms and term sets is that a group is a security boundary. A group contributor can manage the term sets in the groups and create new term sets. All users who have access to a term set under a group can see all of the other term sets—even if they don’t have rights to manage the other term sets. Based on this, you should organize your term sets into groups based on the groups of users who will manage them. For this reason, your taxonomy may correlate to your organizational structure. Let’s take a look at an example.


- Sample SharePoint 2010 EMM (taxonomy) hierarchy

Term Store: In the sample hierarchy shown in the figure above, you can see that there is one term store (called “Taxonomy” for lack of inspiration for a better name). Remember that you can have multiple terms stores, but each term store is stored in a separate SQL Server database.

Under the term store are two groups: Africa and North America. The idea is that these could be significant geographical locations to this particular fictional organization. Remember that the groups are a security boundary, so the users assigned to the Africa group don’t have to have any access to the Egypt group. However, if users are given rights to a term set under one of the groups, they will be able to see the names of all the term sets under that group.

Term Set: Inside the Africa group there are two term sets: South Africa and Egypt.

Terms: At the top level, the South Africa term set contains the terms Cape Town, Johannesburg and Joburg. Terms can be nested seven levels deep. In this case, the Cape Town term contains the child term “Newlands” (a neighbourhood in Cape Town), and that term contains the child term “Ravensberg Avenue” (the street I lived on in Cape Town).

When you’re creating your managed terms, you’re free to identify synonyms; you can also specify which is the preferred term so that when a user types in “Joburg,” she will be asked to assign the term “Johannesburg.”

Here are a couple more quick points to keep in mind:

- You can specify a custom sort order for terms, so it isn’t necessary to show them in alphabetical order.
- Term sets can be open or closed. Open sets allow all users to add terms. Terms can only be added to closed sets by users who are contributors to the group.
- In addition to terms, SharePoint 2010 EMM contains keywords. Keywords aren’t restricted, so they can be used informally to create “folksonomy,” but keywords can be promoted to managed terms.

If you’ve been tasked with creating the taxonomy for your EMM hierarchy, keep these points in mind, but I strongly recommend that you also take advantage of the articles and the worksheets available on TechNet.

Note: You can see the taxonomy terms in a hidden list: http://servername/Lists/TaxonomyHiddenList

[Disclaimer: This information is based on SharePoint 2010 Beta 2 and may differ from the RTM build.]


Anonymous said...

Do Microsoft deliver Sharepoint 2010 with a pre-defined term store, or do we have to manually insert terms?

Stephen Cawood said...

The term store will be empty.

You can use the CSV import option to create your hierarchy in a program such as Excel and then import it into SharePoint.

But whether you use the term store UI, a custom application, or CSV import, you'll need to create the taxonomy yourself.

SharePointFrank said...

You can buy taxonomies for almost any topics, ready to import into SharePoint, from 3rd party vendors here: