Yes, but that’s easily handled with a trigger. My first implementation actually had a regular join table of items_tags which used a trigger to update the items.

Yes, but that’s easily handled with a trigger. My first implementation actually had a regular join table of items_tags which used a trigger to update the items.tags intarray. Wasn’t super performant but let us use our existing templates for 1-many to implement the UI. Nowadays you can just use a tagging component with integrated search for the UI.