How to update content type to include additional lookup fields for all instances of content type?

Question

I have created a lookup field as a site column in my root site. The field also brings several additional columns showing information from the list. It is used in a root site content type.

I have about 50 document libraries that use this content type.

If I update the field to bring more fields from the list, this doesn't get updated in the document libraries.

I know this is 'standard' behaviour, because content types in libraries are 'copies' of the original one, but I am trying to overcome this and update all my content types in the respective libraries.

Answer 1

When you edit the site column, there is a choice to "Update Lists" which should propagate the change to all lists using that column (at the cost of removing any customizations made in those lists). If you are making the change programmatically rather than through the SharePoint UI, the Update method takes a Boolean to specify if you want to push the change out to the lists.

Answer 2

[Found this answer elsewhere]

I think I 've found the source of this behaviour. It might have been so that I originally deployed this field with a property Sealed=true through a feature.

Then afterwards I changed that feature definition. (And I now am aware of that you should never do just that) Redeployed etc. anyhow, it seems that my list content type instance still feels that this particular field is sealed and that's probably why it won't take any changes.

So it can probably only be fixed through code..