db = db.getSiblingDB( "db1" ); db.col1.drop(); const docs = []; for (let i = 0; i < 66600; i++) { docs.push({ SessionId: `OTHER_${ String (i).padStart(8, "0" )}`, Expiration: new Date(Date.now() - i * 60000), SubjectId: `user_${i % 1000}` }); } db.col1.insertMany(docs); db.col1.createIndex({ Expiration: 1, SessionId: 1 }); db.col1.createIndex({ Expiration: -1, SubjectId: 1 }); db.col1.find( { SessionId: "NON_EXISTING_SESSION" }, { Expiration: 1, SubjectId: 1, _id: 0 } ).sort({ Expiration: -1 }).limit(1).explain( "allPlansExecution" );