BCS External List Limitations

One of the big features for Share Point 2010 (and for building OBAs) is the Business Connectivity Services (BCS).

There are a number of features that are missing when you create an External List based on an External Content Type. This can cause a lot of issues with end users because even though it looks exactly like a normal list it might not behave exactly like a normal list (or at least have some features missing).Here are those.

●      Workflows cannot be configured on External Lists

●      Cannot create Information Management Policies

●      No versioning or version history

●      No Inline Editing or Datasheet View

●      No ratings

●      No ability to Export to Excel, Create Visio Diagram, Open with Access or Open with Project

●      No REST access through ListData.svc to External Lists

●      No RSS Feeds

●      No Item Level Permissions

●      No item or field level validation

●      No Lookups

●      No attachments

So, let’s describe all

●      Workflows cannot be configured on External Lists

Unfortunately as you can see you cannot actually run a workflow on an external list. You neither have the option to define any workflows nor can you actually start one. Now this is even if the workflow that you are thinking of defining will not alter the External List item in anyway, doesn’t matter, External List = No Workflows!

●      Cannot create Information Management Policies

When we go to “List Settings  Information management policy settings” of external list, you will see the following error. That means, we can’t create any management policy for external list.

●      No versioning or version history

You cannot version or see version history for an External List. Now this does make sense since in many external systems there is no concept of versions.

●      No Inline Editing or Datasheet View

Inline editing allows you to edit list items from within the list view itself, kind of a datasheet view for an individual item. Datasheet view is a way where you can easily change metadata for multiple items. Neither of these is available.

●      No Rating

This does suck but you cannot rate any items in an external list.

●      No ability to Export to Excel, Create Visio Diagram, Open with Access or Open with Project

Some of these are not available to all list types (Create Visio Diagram or Open with Project for example) but all standard lists are able to be exported to Excel or opened with Access. This is a real shame I think because exporting to Excel is an oft use feature that will be missed by users.

●      No REST access through ListData.svc to External Lists

You can’t access an External List though REST.

●      No RSS Feeds

No RSS Feeds are available either

●      No Item Level Permissions

You also cannot configure item level permissions for External Lists.

●      No item or field level validation

So as you can see there are quite a few limitations that one should be aware of. The thing that is concerning is that from a users perspective you can’t actually tell that a list is external and without all these things being available this can lead to some confusion. But it is out of the box functionality after all and with a little SharePoint Designer and XSL magic you might not be in the situation to expose external lists anyway.

●      No Lookups

Unfortunately the only thing that you can do a look up on in an external list is on the ID column, anything else and you are out of luck.

●      No Attachments

No attachments either. (Attachment option is disabled)