MongoDB में Document के Fields Access करना

Document में fields access करने के लिए simply find() का उपयोग करें।

Collection बनाना

> db.demo565.insertOne(
... {
...   id:101,
...   Name:"David",
...   "CountryName":"US"
... }
... );
{ "acknowledged" : true, "insertedId" : ObjectId("5e90896739cfeaaf0b97b577") }
> db.demo565.insertOne(
... {
...   id:102,
...   Name:"Carol",
...   "CountryName":"UK"
... }
... );
{ "acknowledged" : true, "insertedId" : ObjectId("5e90896839cfeaaf0b97b578") }
> db.demo565.insertOne(
... {
...   id:103,
...   Name:"Sam",
...   "CountryName":"AUS"
... }
... );
{ "acknowledged" : true, "insertedId" : ObjectId("5e90896839cfeaaf0b97b579") }

सभी Documents Display करना

> db.demo565.find();

Output:

{ "_id" : ObjectId("5e90896739cfeaaf0b97b577"), "id" : 101, "Name" : "David", "CountryName" : "US" }
{ "_id" : ObjectId("5e90896839cfeaaf0b97b578"), "id" : 102, "Name" : "Carol", "CountryName" : "UK" }
{ "_id" : ObjectId("5e90896839cfeaaf0b97b579"), "id" : 103, "Name" : "Sam", "CountryName" : "AUS" }

Fields Access करने का Query

> db.demo565.find({"Name":"Carol",CountryName:"UK"},{Name:1});

Output:

{ "_id" : ObjectId("5e90896839cfeaaf0b97b578"), "Name" : "Carol" }

व्याख्या: find(query, projection) में first parameter query filter है (Name="Carol" AND CountryName="UK"), second parameter projection है (Name:1 मतलब केवल Name field include करें, _id default included रहता है)।