Craft has a powerful engine for relating elements to one another... on the front end. However, content authors can't see what is related in the CP.
The use case that prompted this was showing Products < > Categories. The client wanted to see/add products to a category, and then on the product, see what categories have been applied.
But we all have uses cases, to show:
Entries < > Products
Entries < > Users
And more.
As a feature request, perhaps there could be an option when setting up a field to show all element relations.
Maybe with a table view with title, element type, CP link (perhaps customisable columns).
This way content authors can clearly see how their content is related in the CP.
Powerful relations, front and back ends.
Kindof related to #3907, but I鈥檒l leave this open as all you鈥檙e asking for it to _see_ the relations, which would certainly be easier to implement than actually _managing_ the relations from the other end.
In the meantime, check out the Relations plugin, which provides a field type that displays reverse relations.
You have a good point, the client would really want to view/add/delete the related elements, from both sides. Overall I think it would be very intuitive for content authors (who never know where to go in the CMS to do something) and add to their love of Craft.
You don't even need a plugin to _display_ related entries any more. You can make use of the new UI Elements feature in Craft to create a list of related elements in the edit panel: http://craftsnippets.com/articles/using-template-ui-elements-to-extend-craft-cms-control-panel#displaying-reverse-element-relations
I agree that it would be useful to _manage_ reverse relations, but that's a different issue.
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You have a good point, the client would really want to view/add/delete the related elements, from both sides. Overall I think it would be very intuitive for content authors (who never know where to go in the CMS to do something) and add to their love of Craft.