NOTE: There's a newer version of this tool

"Show Schema Map" Tools

You should take a look at it instead of continuing on with this outdated post.

Mark Stanger has a great article over on the ServiceNowGuru site which explains how to create a UI Action that will popup a schema map to show you the table relationships from a form. It's a great tool and I use it constantly, but I've always thought it would be helpful to do it from a list view as well.

So, I created a Context Menu (https://wiki.servicenow.com/index.php?title=Context%5FMenus) that does the trick, even on related lists:

Here is how you set it up: