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Find and Group

If I have the following documents in my collection

{ "_id" : 1, "domainName" : "test1.com", "hosting1" : "hostgator.com",    "hosting2" : "hostgator.com",    sID : 1}
{ "_id" : 2, "domainName" : "test2.com", "hosting1" : "cloud.google.com", "hosting2" : "aws.amazon.com",   sID : 2}
{ "_id" : 3, "domainName" : "test3.com", "hosting1" : "aws.amazon.com",   "hosting2" : "cloud.google.com", sID : 2}

Suppose I want to find "cloud.google.com" in hosting1 or hosting2

I would write a query like

db.chats.find({$or : [{ hosting1 : 'cloud.google.com'}, { hosting2 : 'cloud.google.com'}]}).pretty();

this will give me two entries as below

{ "_id" : 2, "domainName" : "test2.com", "hosting1" : "cloud.google.com", "hosting2" : "aws.amazon.com",   sID : 2}
{ "_id" : 3, "domainName" : "test3.com", "hosting1" : "aws.amazon.com",   "hosting2" : "cloud.google.com", sID : 2}

Suppose I want to find and group by "sID" field

Suppose I want to find "cloud.google.com" on hosting1 or hosting2, and then GROUPBY on "sID": 2 means

My result will be

{ "_id" : 2, "domainName" : "test2.com", "hosting1" : "cloud.google.com", "hosting2" : "aws.amazon.com",   sID : 2}

How to write a request for my above requirement

My sql request will be

SELECT *
FROM chats
WHERE (hosting1 = 'cloud.google.com' OR hosting2 = 'cloud.google.com')
GROUPBY sID;

I went through the mongoDB $ group, but I could not get it to work

Could you give me an idea of ​​how to achieve this. Your help is greatly appreciated. Thank.

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2 answers

Mongo Aggregation, $first $$ ROOT :

db.collection.aggregate({
    $match: {
    $or: [{
        "hosting1": "aws.amazon.com"
    }, {
        "hosting2": "aws.amazon.com"
    }]
    }
}, {
    $group: {
    "_id": "$sID",
    "domain": {
        $first: "$$ROOT"
    }
    }
})

$$ ROOT - . , .

$first - , , . , .

, -

db.collection.find({
    $or: [{
    hosting1: 'cloud.google.com'
    }, {
    hosting2: 'cloud.google.com'
    }]
}).limit(1)
+3

. $limit.

db.collection.aggregate(
    [
      { $match: 
        { 
          $or : [
                  { hosting1 : 'cloud.google.com' }, 
                  { hosting2 : 'cloud.google.com'}
          ]
        }
      },
      { $limit: 1 }
    ]
)

, find.

db.collection.find({ 
    $or :[
           { hosting1 : 'cloud.google.com'},
           { hosting2 : 'cloud.google.com'}]
     }
).limit(1)
+3

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