javascript - Unknown operator: $and in MongoDB - Stack Overflow

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I am querying mongodb through node.js code. My mongo documents collection (Patients Collection) has the following structure:+

Patient collection

{ 
    "_id" : ObjectId("59e5c28f37ce021e142e7ead"), 
    "MRN" : "00126389", 
    "Family_Name" : "Jones", 
    "First_Name" : "Lydia", 
    "Father_Name" : "Bob", 
    "Maiden_Name" : "", 
    "Mother_Name" : "n/a", 
    "Spouse_Name" : "", 
    "Address" : "", 
    "Telephone_Nbr" : "", 
    "Patient_Visit" : {
        "Department" : "ER", 
        "Hospital_Status" : "Active", 
        "Case_Nbr" : "17", 
        "Admission_Date" : "01/04/2011 12:00:00 AM", 
        "Admission_Time" : "14:02"

    }
}

My query execution code is presented below:

mongoClient.connect(mongoConstr, function(err, db) {
    if (err) throw err;
    var query = {
        $and: [{
            "Patient_Visit.Department": "ER"
        }, {
            $or: [{
                "Patient_Visit.Hospital_Status": "Active Left"
            }, {
                "Patient_Visit.Hospital_Status": "Active"
            }]
        }]
    };
    var cursor = db.collection("tbl_Patients").find({
        query
    });
    cursor.forEach(function(doc) {
        console.log(JSON.stringify(doc));
    }, function(err) {
        db.close();
        throw (err);
    });
});

When the request is executed I get the following error:

MongoError: unknown operator: $and

Any help would be appreciated.

I am querying mongodb through node.js code. My mongo documents collection (Patients Collection) has the following structure:+

Patient collection

{ 
    "_id" : ObjectId("59e5c28f37ce021e142e7ead"), 
    "MRN" : "00126389", 
    "Family_Name" : "Jones", 
    "First_Name" : "Lydia", 
    "Father_Name" : "Bob", 
    "Maiden_Name" : "", 
    "Mother_Name" : "n/a", 
    "Spouse_Name" : "", 
    "Address" : "", 
    "Telephone_Nbr" : "", 
    "Patient_Visit" : {
        "Department" : "ER", 
        "Hospital_Status" : "Active", 
        "Case_Nbr" : "17", 
        "Admission_Date" : "01/04/2011 12:00:00 AM", 
        "Admission_Time" : "14:02"

    }
}

My query execution code is presented below:

mongoClient.connect(mongoConstr, function(err, db) {
    if (err) throw err;
    var query = {
        $and: [{
            "Patient_Visit.Department": "ER"
        }, {
            $or: [{
                "Patient_Visit.Hospital_Status": "Active Left"
            }, {
                "Patient_Visit.Hospital_Status": "Active"
            }]
        }]
    };
    var cursor = db.collection("tbl_Patients").find({
        query
    });
    cursor.forEach(function(doc) {
        console.log(JSON.stringify(doc));
    }, function(err) {
        db.close();
        throw (err);
    });
});

When the request is executed I get the following error:

MongoError: unknown operator: $and

Any help would be appreciated.

• javascript
• node.js
• mongodb

Share Improve this question Follow edited Oct 20, 2017 at 8:38 Derek 朕會功夫 94.5k4545 gold badges198198 silver badges253253 bronze badges asked Oct 20, 2017 at 8:37 Elie AsmarElie Asmar 3,16566 gold badges2020 silver badges3232 bronze badges 5

• which version of Mongo you are using.? – Rijad Rahim Commented Oct 20, 2017 at 8:41
• 3.4.5-rc0-4-g4db4a7c as per db.version() return value – Elie Asmar Commented Oct 20, 2017 at 8:45
• 2 Someone has already attempted to answer you, Despite getting the callback part wrong the issue is you should be doing .find(query) and not .find({ query }). That's an ES6 syntax being expanded to find({ "query": query }) and you don't want that. Hence the error. – Neil Lunn Commented Oct 20, 2017 at 8:48
• @ElieAsmar - Remove the additional {} in your query. Modified query part var cursor = db.collection("tbl_Patients").find(query); – Clement Amarnath Commented Oct 20, 2017 at 8:48
• 1 Not the issue but even query can be rewritten as { "Patient_Visit.Department": "ER", "Patient_Visit.Hospital_Status": { "$in": ["Active Left", "Active"] } }. $and is "implicit" in ALL MongoDB query arguments and rarely ever needed explicitly. Also $in is a much shorter version of $or when you are applying the condition to the same property. – Neil Lunn Commented Oct 20, 2017 at 8:59

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 10

Replace the {query} with query.

var cursor = db.collection("tbl_Patients").find(query);

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