use admin db.runReadCommand({ setFeatureCompatibilityVersion:"3.4"}) use testdb db.createCollection("testcollection",{collation:{locale: "sv", strength:1, numericOrdering:true}}) db.testcollection.insert( { data: "test" } ) db.testcollection.insert( { data: "TEST" } ) > db.testcollection.find({ data: { $eq: "test" } }) { "_id" : ObjectId("58a461e0aa464d5347f68ecb"), "data" : "test" } { "_id" : ObjectId("58a461f0aa464d5347f68ecc"), "data" : "TEST" } > db.testcollection.find({ data: { $ne: "test" } }) { "_id" : ObjectId("58a461f0aa464d5347f68ecc"), "data" : "TEST" } >//the above query should not result in any document but it returns the one with uppercase.