如何在Node JS中从Mongodb查询两个集合

Question

I have VisitModel that has saved the visit of various users to different visiter locations.

{ 
    "_id" : ObjectId("5bb5d748b8c8a07fee6b4437"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(500), 
    "hrno" : NumberInt(200900410), 
    "lastUpdationTime" : ISODate("2018-10-04T09:03:04.619+0000"), 
    "mobileNo" : "9413394574", 
    "name" : "Hirdesh Sharma", 
    "simInventory" : NumberInt(10), 
    "ssa" : "cojp", 
    "visitedRetailer" : "7597000662", 
    "visitLocation" : {
        "lat" : "26.9140156", 
        "lng" : "75.7997062"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb5ea682b955e0961e55b24"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(10), 
    "hrno" : NumberInt(200900410), 
    "lastUpdationTime" : ISODate("2018-10-04T10:24:40.180+0000"), 
    "mobileNo" : "9413394574", 
    "name" : "Hirdesh Sharma", 
    "simInventory" : NumberInt(10), 
    "ssa" : "cojp", 
    "visitedRetailer" : "7597000662", 
    "visitLocation" : {
        "lat" : "26.9140203", 
        "lng" : "75.7997103"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb71766edeebb1682902c5a"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(0), 
    "hrno" : NumberInt(200900410), 
    "lastUpdationTime" : ISODate("2018-10-05T07:48:54.566+0000"), 
    "mobileNo" : "9413394574", 
    "name" : "Hirdesh Sharma", 
    "simInventory" : NumberInt(0), 
    "ssa" : "cojp", 
    "visitedRetailer" : "123456789", 
    "visitLocation" : {
        "lat" : "26.913970499999998", 
        "lng" : "75.799515"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb71991edeebb1682902c5b"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(0), 
    "hrno" : NumberInt(200900410), 
    "lastUpdationTime" : ISODate("2018-10-05T07:58:09.241+0000"), 
    "mobileNo" : "9413394574", 
    "name" : "Hirdesh Sharma", 
    "simInventory" : NumberInt(0), 
    "ssa" : "cojp", 
    "visitedRetailer" : "1234567890", 
    "visitLocation" : {
        "lat" : "26.9140163", 
        "lng" : "75.7997024"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb72c28edeebb1682902c5d"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(10000), 
    "hrno" : NumberInt(200901869), 
    "lastUpdationTime" : ISODate("2018-10-05T09:17:28.825+0000"), 
    "mobileNo" : "9413395846", 
    "name" : "Dharmendra Soni", 
    "simInventory" : NumberInt(15), 
    "ssa" : "Circle Office", 
    "visitedRetailer" : "0000000000", 
    "visitLocation" : {
        "lat" : "26.8922714", 
        "lng" : "75.8042042"
    }
}


// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb72e50edeebb1682902c5e"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(5000), 
    "hrno" : NumberInt(200901869), 
    "lastUpdationTime" : ISODate("2018-10-05T09:26:40.371+0000"), 
    "mobileNo" : "9413395846", 
    "name" : "Dharmendra Soni", 
    "simInventory" : NumberInt(10), 
    "ssa" : "Circle Office", 
    "visitedRetailer" : "9414002070", 
    "visitLocation" : {
        "lat" : "26.8922503", 
        "lng" : "75.8041773"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb72f49edeebb1682902c5f"), 
    "__v" : NumberInt(0), 
    "ctopamount" : 1.5, 
    "hrno" : NumberInt(200901869), 
    "lastUpdationTime" : ISODate("2018-10-05T09:30:49.843+0000"), 
    "mobileNo" : "9413395846", 
    "name" : "Dharmendra Soni", 
    "simInventory" : null, 
    "ssa" : "Circle Office", 
    "visitedRetailer" : "7597000559", 
    "visitLocation" : {
        "lat" : "26.8922608", 
        "lng" : "75.8041638"
    }
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5bb759e7edeebb1682902c63"), 
    "__v" : NumberInt(0), 
    "ctopamount" : NumberInt(0), 
    "hrno" : NumberInt(198911286), 
    "lastUpdationTime" : ISODate("2018-10-05T12:32:39.394+0000"), 
    "mobileNo" : "9413395614", 
    "name" : "Shankara lal meena", 
    "simInventory" : NumberInt(0), 
    "ssa" : "Chittorgarh", 
    "visitedRetailer" : "7597000559", 
    "visitLocation" : {
        "lat" : "24.038592", 
        "lng" : "74.7767928"
    }
}
}

i have another model which has a saved database of RetailerLocation which has saved the filed retailer name ,address ,retailer number and a location

{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a029"), 
    "Name of Retailer" : "Karan Singh", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.8122376, 
        "lng" : 75.7783984
    }, 
     "Retailernumber"  : "7597000559"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02a"), 
    "Name of Retailer" : "HANUMAN PRASAD", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.9142872, 
        "lng" : 75.7431824
    }, 
     "Retailernumber"  : "7597000632"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02b"), 
    "Name of Retailer" : "Karan Singh", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.9039945, 
        "lng" : 75.8325143
    }, 
     "Retailernumber"  : "7597000633"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02c"), 
    "Name of Retailer" : "kunal hemani", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.931319, 
        "lng" : 75.8201112
    }, 
    "Retailernumber" : "7597000638"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02d"), 
    "Name of Retailer" : "kumawat floor mill", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.8592253, 
        "lng" : 75.7851659
    }, 
    "Retailernumber": "7597000662"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02e"), 
    "Name of Retailer" : "care point", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.9247296, 
        "lng" : 75.7894896
    }, 
    "Retailernumber" : "7597000708"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a02f"), 
    "Name of Retailer" : "SAYED MOBILE", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.933338, 
        "lng" : 75.8074372
    }, 
    "Retailernumber" : "7597000718"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a030"), 
    "Name of Retailer" : "jaipur moters", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.9187819, 
        "lng" : 75.8102266
    }, 
    "Retailernumber" : "7597000773"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a031"), 
    "Name of Retailer" : "sona telecom", 
    "SSA" : "JAIPUR", 
    "savedLocation" : {
        "lat" : 26.9212756, 
        "lng" : 75.8085795
    }, 
    "Retailernumber" : "7597000776"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a032"), 
    "Name of Retailer" : "sangam mobile", 
    "SSA" : "JAIPUR", 
   "savedLocation" : {
        "lat" : 26.9194859, 
        "lng" : 75.8078163
    }, 
    "Retailernumber" : "7597000785"
}
// ----------------------------------------------
{ 
    "_id" : ObjectId("5c864a80498ceb2d94a8a033"), 
    "Name of Retailer" : "bombay  collection", 
    "SSA" : "JAIPUR", 
   "savedLocation" : {
        "lat" : 26.8564543, 
        "lng" : 75.8207683
    }, 
   "Retailernumber": "7597000792"
}

now i want to display the data as following

{
    "ctopamount" : NumberInt(500), 
    "hrno" : NumberInt(200900410), 
    "mobileNo" : "9413394574", 
    "name" : "Hirdesh Sharma", 
    "simInventory" : NumberInt(10), 
    "ssa" : "cojp", 
    "visitedRetailer" : "7597000662", 
    "visitLocation" : {
        "lat" : "26.9140156", 
        "lng" : "75.7997062"
    }
  "savedLocation" : {
        "lat" : "26.9140156", 
        "lng" : "75.7997062"
    }
}

where the saved location should be fetched from RetailerLocation collection based on visitedRetailer=RetailerMobile

Answer 1

In your visit model instead of saving the visit location, you can directly save the object id of the retailers from the retailer location. Then you can just use the populate the data. Here is the reference to the populate in Mongoose

I hope this helps.

Answer 2

Try with this.

Write aggregate function in visitModel and lookup to RetailerLocation.

Test1 -> visitModel Test2 ->RetailerLocation

db.getCollection('Test1').aggregate([
{
$lookup:{
    from:"Test2",
    localField:"visitedRetailer",
    foreignField:"Retailernumber",
    as:"retailerDetails"
    }
},
{
$unwind:{
    path:"$retailerDetails",
    preserveNullAndEmptyArrays:true
    }
},
{
$project:{
            "ctopamount" :1, 
            "hrno" : 1, 
            "mobileNo" : 1, 
            "name" : 1, 
            "simInventory" :1, 
            "ssa" : 1, 
            "visitedRetailer" : 1, 
            "visitLocation" : 1,
            "savedLocation" : "$retailerDetails.savedLocation"
    }
}
])

Answer 3

I don't have access to comment but with respect to @Ashwanth Madhav 's answer, you can do the same in mongoose.

Test1.aggregate([{
$lookup:{
from:"Test2",
localField:"visitedRetailer",
foreignField:"Retailernumber",
as:"retailerDetails"
}
},
{
$unwind:{
path:"$retailerDetails",
preserveNullAndEmptyArrays:true
}
},
{
$project:{
        "ctopamount" :1, 
        "hrno" : 1, 
        "mobileNo" : 1, 
        "name" : 1, 
        "simInventory" :1, 
        "ssa" : 1, 
        "visitedRetailer" : 1, 
        "visitLocation" : 1,
        "savedLocation" : "$retailerDetails.savedLocation"
}}
                ]).exec(function (err,fetcheddata) {

    if( _.isNull(err) && fetcheddata.length > 0 ){
        var response = genRes.generateResponse(true,"found successfully");
        callback(response,fetcheddata);
    }
    else if( fetcheddata==undefined || transactions.length == 0 ){
        var response = genRes.generateResponse(false,"No Data found");
        callback(response,null);
    }
    else{
        var response = genRes.generateResponse(false,"there occurred some error : "+err);
        callback(response,null)
    }
})
};