mongodb - Mongo distinct query returns several records one of which is "". But find null fails to find it -

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i ran distinct query on collection. query syntax:

db.collection.distinct("dict.field")

i got set of results - 1 of "" (null).

i tried find record had null value field in question:

db.collection.find({"dict.field": null})

to surprise, no record found.

no indexes set on collection other _id.

the field in question dictionary.

what missing?

you should db.collection.find({"dict.field": ""}) instead. null , string ("") considered different datatypes.

https://docs.mongodb.com/manual/reference/bson-types/


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