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A Collection can have up to 100,000 ( ? ) Items.
There can be at most 10,000 ( ? ) Collections in a Library
A single Item may belong to at most 100 Collections
This is largely to make sure that we can quickly do updates to Collections indexing that involve their contents, e.g. “sort Collections by their last modified Item”
Items have no manually selected ordering within a Collection.
Collections can overlap. An Item can belong to multiple Collections.
Collections do not nest. Collections are not Items. A Collection can be a superset of another Collection, but Collection cannot contain another Collection as one of its elements.
Collections are not publishable entities themselves.
They contain things that can be published (like Components), but there is no “draft” vs. “published” version of a Collection. Changes to Collection metadata like its name, description, or contents are saved immediately.
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