Thanks @Chanel but my question wasn't how to GET items in a given category but how to PUT them to order them.
Sorry about the confusion! The order that you associate the items is reflected in the current ordering. That is, when you associate Item 2, Item 3 and then Item 1 with Category A, then the list of items will appear as [Item 2, Item 3, Item 1]. The only way to change this order is to manually hand sort them (as you've pointed out) or to completely clear the items and re-associate them in the "correct" order. Clearly not efficient, but that list is only meant to keep track of the item associations themselves, not to be directly viewed or user-friendly.
Thanks @Chanel. Let me see if I have the right. If I have 1600 items in 23 categories and I want to order the items alphabetically in just 5 categories, I need to remove the associations from all 1600 items and then add them back into the all of the correct categories alphabetically?
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