[Python] MongoDB count_documents() returns 19 but find() returns empty list - Replica Set...

Good morning everyone,

I'm experiencing a consistency issue with MongoDB in production. I have a 3-node replica set deployed on OVH, and sometimes count_documents() and find() return different results for the exact same query. This issue happens always whene there are write operations on the mongo, but I doubt it could be normal.. reading and writing operations should stay consistent.

Example:

collection.count_documents(query) returns 19 list(collection.find(query)) returns [] (empty list)

This happens sporadically in production with the same query executed within seconds of each other.

• MongoDB Version: 6.0.23
• Driver: PyMongo (Python) Version 4.8.0
• Deployment: 3-node replica set on OVH
• Query: Same filter used for both operations

What I've Tried

• Verified the query is identical in both operations
• The issue occurs randomly, not consistently
• I tried writeConcern "majority" + readConcern "majority"
• Boths operations are executed inside the same session & transaction

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