MongoDB query to collectively match intersection of documents against a field

MongoDBDatabaseBig Data Analytics

For this, use aggregate(). Let us first create a collection with documents −

> db.demo393.insertOne(
...    {
...       Id1: "1",
...       Name: "Chris",
...       Id2: "100"
...    }
... );
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e5e6dd522064be7ab44e804")
}
> db.demo393.insertOne(
...    {
...       Id1: "1",
...       Name: "Chris",
...       Id2: "101"
...    }
... );
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e5e6dd522064be7ab44e805")
}
> db.demo393.insertOne(
...    {
...       Id1: "3",
...       Name: "Chris",
...       Id2: "100"
...    }
... );
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e5e6dd522064be7ab44e806")
}
> db.demo393.insertOne(
...    {
...       Id1: "3",
...       Name: "Mike",
...       Id2: "101"
...    }
... );
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5e5e6dd522064be7ab44e807")
}

Display all documents from a collection with the help of find() method −

> db.demo393.find();

This will produce the following output −

{ "_id" : ObjectId("5e5e6dd522064be7ab44e804"), "Id1" : "1", "Name" : "Chris", "Id2" : "100" }
{ "_id" : ObjectId("5e5e6dd522064be7ab44e805"), "Id1" : "1", "Name" : "Chris", "Id2" : "101" }
{ "_id" : ObjectId("5e5e6dd522064be7ab44e806"), "Id1" : "3", "Name" : "Chris", "Id2" : "100" }
{ "_id" : ObjectId("5e5e6dd522064be7ab44e807"), "Id1" : "3", "Name" : "Mike", "Id2" : "101" }

Following is the query to collectively match intersection of documents against a field −

> db.demo393.aggregate([
...    { "$match": { "Name": "Chris" } },
...    { "$group": {
...       "_id": "$Id1",
...       "docs": { "$push": "$$ROOT" },
...       "count": { "$sum": 1 }
...    }},
...    { "$match": {
...       "count": { "$gt": 1 },
...       "docs": {
...          "$all": [
...             { "$elemMatch": { "Id2": "100" } },
...             { "$elemMatch": { "Id2": "101" } }
...          ]
...       }
...    }}
... ])

This will produce the following output −

{ "_id" : "1", "docs" : [ { "_id" : ObjectId("5e5e6dd522064be7ab44e804"), "Id1" : "1", "Name" : "Chris", "Id2" : "100" }, { "_id" : ObjectId("5e5e6dd522064be7ab44e805"), "Id1" : "1", "Name" : "Chris", "Id2" : "101" } ], "count" : 2 }
raja
Published on 02-Apr-2020 17:49:51
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