MongoEngine / MongoEngine/mongoengine

update() function disregards limit()

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Bug
Dominant language
Python
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Avg merge
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Merged PRs (30d)
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Description

Lets say I have a 10 documents of Item in the database.

Lets retrieve 3 documents of Item matching some condition using limit().

documents = Item.objects(somefield=somecondition).limit(3)

Now if I do

documents.update(), mongoengine updates all the documents in the database matched by the query not just the 3 documents I have limited my query to.

Hope this gets fixed.

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Research direction

Start by reproducing the issue with the Item.objects(...).limit(3) query followed by documents.update(). Trace the update entry point and its query construction to determine how the limit is lost; done means only the three limited documents are updated, with regression coverage for this example.

Written by the indexing model from the issue text.

Assessment

Tech stack
mongodb, python
Domain
databases
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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