执行mongo命令时出错

Question

I have a created a collection with following command:

db.device_states.documentKey.insert({"device":"nest_kitchen_thermo"})

When I try to execute below command I get an error:

db.device_states.watch( {
     $match: {
             "documentKey.device": {
                   $in : [ "nest_kitchen_thermo"]
             },
             operationType: "insert"
     }
});

syntax ERROR: missing:after property id:

The updated collection looks like that:

{ 
    _id: <resume_token>,
    operationType: 'insert',
    ns: {db:'example',coll:"device_states"},
    documentKey: { device:'nest_kitchen_thermo'},
    fullDocument: { 
       _id : ObjectId(),
       device: 'nest_kitchen_thermo',
       temp: 68
    }
}

Answer 1

In Mongo shell, there is no such querying attribute watch . $match is part of aggregation pipeline and it should be used within the aggregate operation.

Modified query(Mongo Shell) is

db.device_states.documentKey.aggregate([
  { $match:
    { 
      "device": { $in: ["nest_kitchen_thermo"] }, 
      operationType: "insert"
    }
  }
]);