In this article , I will explore the BCS External List Limitations. but let me first tell you about the major issue that I got it.
In external list, If the number of retrieving items become more than 2000 items,It will not work properlly (take more time) to render the list itmes and may be stuck!
Fortunately, you can exceed the default max limit (2.000 items) using Power Shell to the absolute max (25.000 items) . but unfortunately, if you also tried to do this , the performance issue will still persist !! Moreover, exceeding the default max size is not recommended based on Microsoft support response.
I think most of the readers don’t continue reading because the previous major limitation is enough to don’t use the external list if the retrieving items were more than 2000 items.
Anyway, let’s explore other limitations!
- Datasheet view is not available
- Export to Excel option is not available
- Workflows cannot be configured for 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 any way, doesn’t matter, External List = No Workflows!
- Cannot create Information Management Policies (bar codes, auditing, retention or labels)
- This kind of makes sense. I mean you can really declare something a record or move something to another location if you aren’t storing it within SharePoint but it is worth knowing. No IMP’s means no barcodes, auditing, retention or labels.
- Try to add an IMP and this is what you get, I don’t know why it hasn’t been removed from the list options.
- No version 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
- Inline Editing is not available
- 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 Ratings widget
- This does suck but you cannot rate any items in an external list.
- Can’t create Visio Diagrams
- 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.
- Open with Access/Open with Project is not supported
- REST access via ListData.svc to External Lists is not available (All WCF services like RSS feeds are not available)
- Yep, you can’t access an External List through REST…
- There are not Lookups fields.
- 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 Context Menu (ECB) Send To operations.
- Events handlers are not supported.
- LINQ to SharePoint spmetal.exe does not support external lists
- No Item Level Permissions
- No item or field level validation or Formula supported
- 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.
- Document templates are not supported.
- Alerts are not supported.
- Attachments will not be available.
- Additional data connections in InfoPath 2010 list forms not supported.
- U2U CAML Query builder doesn’t work!.
- No Check In / Checks Out options.
- Drafts of items are not supported.
- No Write support for BLOB.
- Metadata based navigation is not supported.
- No RSS Feeds.
Some Improvements in BCS External List SharePoint 2013
- Supports OData.
- Export to Excel option.
- Event Receiver on external lists
- Support for SharePoint Apps.
- Sorting external lists.
- Data Source Filtering.