> db.setProfilingLevel(1, { slowms: 0 }); // Log all queries as slow querys > db.createCollection( "users" ) > db.users.createIndex({ email: 1 }, { unique: true }) > userDoc = { email: "alice@example.com" , name: "Alice" } > session.getDatabase(db.getName()).users.insert(userDoc) // Reports success > session.getDatabase(db.getName()).users.insert(userDoc) // Reports E11000 duplicate key error collection: test.users index: email_1 dup key: { email: "alice@example.com" } .... // Slow query logs. // First insert: ninserted 1 { "t" :{ "$date" : "2025-09-17T13:01:49.093-05:00" }, "s" : "I" , "c" : "COMMAND" , "id" :51803, "ctx" : "conn28" , "msg" : "Slow query" , "attr" :{ "type" : "command" , "ns" : "test.users" , "appName" : "mongosh 2.5.1" , "command" :{ "insert" : "users" , "documents" :[{ "email" : "alice@example.com" , "name" : "Alice" , "_id" :{ "$oid" : "68caf78d2ee4a2979b4fa64c" }}], "ordered" : true , "lsid" :{ "id" :{ "$uuid" : "7a5eb408-41e8-40d9-9c04-e6d2d229ebcd" }}, "txnNumber" :1, "$clusterTime" :{ "clusterTime" :{ "$timestamp" :{ "t" :1758132082, "i" :1}}, "signature" :{ "hash" :{ "$binary" :{ "base64" : "AAAAAAAAAAAAAAAAAAAAAAAAAAA=" , "subType" : "0" }}, "keyId" :0}}, "$readPreference" :{ "mode" : "primaryPreferred" }, "$db" : "test" }, "totalOplogSlotDurationMicros" :149, "ninserted" :1, "keysInserted" :2, "numYields" :0, "reslen" :230, "locks" :{ "ParallelBatchWriterMode" :{ "acquireCount" :{ "r" :3}}, "FeatureCompatibilityVersion" :{ "acquireCount" :{ "r" :5, "w" :2}}, "ReplicationStateTransition" :{ "acquireCount" :{ "w" :6}}, "Global" :{ "acquireCount" :{ "r" :5, "w" :2}}, "Database" :{ "acquireCount" :{ "r" :2, "w" :2}}, "Collection" :{ "acquireCount" :{ "r" :2, "w" :2}}}, "flowControl" :{ "acquireCount" :1}, "readConcern" :{ "provenance" : "implicitDefault" }, "writeConcern" :{ "w" : "majority" , "wtimeout" :0, "provenance" : "implicitDefault" }, "waitForWriteConcernDurationMillis" :13, "storage" :{}, "remote" : "127.0.0.1:52614" , "protocol" : "op_msg" , "durationMillis" :17}} // Second insert: ninserted: 0 { "t" :{ "$date" : "2025-09-17T13:01:51.685-05:00" }, "s" : "I" , "c" : "COMMAND" , "id" :51803, "ctx" : "conn28" , "msg" : "Slow query" , "attr" :{ "type" : "command" , "ns" : "test.users" , "appName" : "mongosh 2.5.1" , "command" :{ "insert" : "users" , "documents" :[{ "email" : "alice@example.com" , "name" : "Alice" , "_id" :{ "$oid" : "68caf78f2ee4a2979b4fa64d" }}], "ordered" : true , "lsid" :{ "id" :{ "$uuid" : "7a5eb408-41e8-40d9-9c04-e6d2d229ebcd" }}, "txnNumber" :2, "$clusterTime" :{ "clusterTime" :{ "$timestamp" :{ "t" :1758132109, "i" :1}}, "signature" :{ "hash" :{ "$binary" :{ "base64" : "AAAAAAAAAAAAAAAAAAAAAAAAAAA=" , "subType" : "0" }}, "keyId" :0}}, "$readPreference" :{ "mode" : "primaryPreferred" }, "$db" : "test" }, "totalOplogSlotDurationMicros" :280, "ninserted" :0, "numYields" :0, "reslen" :466, "locks" :{ "ParallelBatchWriterMode" :{ "acquireCount" :{ "r" :1}}, "FeatureCompatibilityVersion" :{ "acquireCount" :{ "r" :2, "w" :1}}, "ReplicationStateTransition" :{ "acquireCount" :{ "w" :4}}, "Global" :{ "acquireCount" :{ "r" :2, "w" :1}}, "Database" :{ "acquireCount" :{ "w" :1}}, "Collection" :{ "acquireCount" :{ "w" :1}}}, "flowControl" :{ "acquireCount" :1}, "readConcern" :{ "level" :"