This is part 1 of a 2 part serious about using the Related Items column in SharePoint 2013.
I ran into an interesting request recently that ended up with an interesting solution. The request that I had was based around connecting a list and a document library. I built a custom list that was used to track deliverables for a project and all of the information about them. At first all actual document deliverables were "attached" to the list item when it was completed. This was not a good approach as attachments are not crawled and indexed. To fix that first issue, I created a separate document library that would hold the deliverables and added a lookup column back the deliverable list. Here are screenshots of the list and library with the lookup column.
This was a good approach to tie the list item and a document together. But then the next question was asked...
If I am on the deliverable list, why can't I see what documents are connected?
While pondering an answer I recalled that there was a new column in SharePoint 2013 called Related Items. I had used that column in the OOTB (out of the box) way with such things as tasks and videos but I had never tried to manipulate it myself. So I first went to try to add that column to my list to test it out but it was not listed as an available column to add...
Getting the Related Items column
This column is part of the hidden group (_Hidden) by default which does not display in the site columns list. This column can be found via the Task content type and updated to a new group. These are the steps to unhide the column:
Navigate to Site Settings and click Site content types in the Web Designer Galleries section.
Under the List Content Types section click on Task.
Click on the Related Items task link.
Click Edit site column.
Change the Group settings from _Hidden to an Existing group (such as Custom Columns).
The Related Items column can now be added to a list or library! So I went ahead and added the column to my deliverable custom list and was ready to start figuring out how to use this column effectively.
In the next part I will discuss how to work with the Related Items column via a SharePoint 2013 workflow created in SharePoint Designer.
Link to part 2
Utilizing the new Related Items column via workflow - Part 2