I have custom slider module.
Within that module you can add items (slides) one by one ( with title, caption, aso.. ).
Now I added a checkbox to the same form.
Only one item (slide) should have that checkbox checked at the same time! I dont want to uncheck it on one item and check it on the next -> this should be automatic. So if I check that checkbox for an item it should remove the checked status in DB from the old one.