Database question - need hints on searching for items not assigned to any collection

Davidmorton7 · 2025-09-28T13:34:41+00:00

I have a pretty big library (~5800 items) and I am interested in identifying all items that are _not_ assigned to one of my collections. Doing it manually with the ctrl key seems labor intensive.
I'm familiar with using an sqlite client. What I'm not finding by browsing tables in my database is an obvious way to do what I'm trying to do. The table collectionItems might be the key, but at first glance, it appears that the item ids of library items that are _not_ assigned to a collection would not appear in that table. Is that correct? If so, then the solution that came mind first was to search the sequence of item ids (1-~5800) and find missing item ids (maybe using something like what this person tried https://stackoverflow.com/questions/1057389/sql-query-to-find-missing-sequence-numbers). I'm looking for suggestions if anybody knows a better way.

tim820 · 2025-09-28T13:43:05+00:00

https://www.zotero.org/support/collections_and_tags#unfiled_items

Edit: Your title says "any collection", so I assumed you don't mean not in a *particular* collection.

abaevbog · 2025-09-29T05:29:48+00:00

You can find all items that are not in a specific collection by using advanced search: https://www.zotero.org/support/searching#advanced_search. Select "Collection" as a condition in the first dropdown, "is not" operator in the second dropdown, and finally the collection you need in the last dropdown. The result should be all items that are not in the collection you selected.

Davidmorton7 · 2025-09-29T13:34:04+00:00

Holy cow that is so simple. I totally forgot about that unfiled items feature. I think that's exactly what I need - something that will generate a list of every item in my library that has not been "filed" (that must be the correct term in Zotero language) in a collection. Thanks!