Convert Lookup to Cross-Site Lookup

[Jeff Childers]

Is it possible to convert a lookup column into a cross-site lookup column?

[Dmitry Kozlov]

Unfortunately, not. But I can suggest you to create a new Cross-site Lookup column and copy values from a simple lookup field to the new Cross-site Lookup field in quick edit mode.

[Jeff Childers]

Got it. The idea came from the "Infowise Color Choice Column" app. In that app, you an select an existing choice field and convert it to a Color Choice Field. I suspect that all that really occurs is a jslink for the field is created to modify the way it renders rather than changing the field itself.

As for copying values, the easiest way to do this would be to use Access and copy the ID of the source list in the first column to the second list and everything will then work properly.

Of course, this does not solve my problem which is that I need the column to be a site column to support creating lists in subsites. I just can't seem to get a list with cross-site lookups to work properly when the list is saved as a template and then re-generated in a subsite.

[Dmitry Kozlov]

Hi Jeff,

I have tested templates of lists with Cross-site Lookup (CSL) columns and it seems they work properly. I created two lists in my root site: Countries and Custom list with CSL field Country linked to Countries. Next, I saved Custom list as template and created a new list in a subsite based in this template. As I see, Country column of a new list still linked to Countries from the root site and works properly on all types of forms.

[Jeff Childers]

I agree that when you use cross-site lookups in the parent list, save the list as a template, and then create a list in a subsite form a template, that the lookups remain connected.

However, the cross-site lookups no longer work correctly. For example, multi-value vields move from the single field format to the old style format with a list on the left and the add/remove buttons. The single lookup field columns no longer have the search and display features.

In other words, it appears that the cross-site lookup column continue to lookup cross-site values; however, their functionality is converted back to a regular lookup column.

[Dmitry Kozlov]

Hello Jeff,

I have just tested it in Office 365 too and it seems everything works correctly: search, multiselection, add new item link etc. Are sure that you create a list based on a template, not a site? Do you have the latest version of Forms Designer and Cross-site Lookup installed?

[rostislav]

We have now implemented this feature and it is available in Cross Site Lookup version 1.4.3. In SharePoint Online you'll need to remove and readd the CSL app, for SharePoint On-premises you'll need to install the new version via the installer.