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AmitDiwan has Published 10740 Articles
AmitDiwan
193 Views
Yes, you can skip some documents using skip() in MongoDB. Use limit() to display how many documents you want to display after skipping some. Let us create a collection with documents −> db.demo682.insertOne({FirstName:"John"}); { "acknowledged" : true, "insertedId" : ObjectId("5ea462a804263e90dac94402") } > db.demo682.insertOne({FirstName:"Sam"}); { "acknowledged" : true, ... Read More
AmitDiwan
243 Views
To get the topmost document, use find() along with limit(). To fetch only a single document, consider using limit(1). Let us create a collection with documents −> db.demo681.insertOne({_id:101, Name:"Chris"}); { "acknowledged" : true, "insertedId" : 101 } > db.demo681.insertOne({_id:102, Name:"Bob"}); { "acknowledged" : true, "insertedId" : 102 } > db.demo681.insertOne({_id:103, ... Read More
AmitDiwan
250 Views
The $and performs a logical AND operation on an array of one or more expressions. Let us create a collection with documents −> db.demo680.insertOne({Values:40}); { "acknowledged" : true, "insertedId" : ObjectId("5ea4461b04263e90dac943fe") } > db.demo680.insertOne({Values:70}); { "acknowledged" : true, "insertedId" : ObjectId("5ea4461e04263e90dac943ff") } > db.demo680.insertOne({Values:[80, 30]}); { ... Read More
AmitDiwan
298 Views
Let us create a collection with documents −> db.demo677.insertOne({Value:10}); { "acknowledged" : true, "insertedId" : ObjectId("5ea421f404263e90dac943f8") } > db.demo677.insertOne({Value:50}); { "acknowledged" : true, "insertedId" : ObjectId("5ea421f704263e90dac943f9") } > db.demo677.insertOne({Value:20}); { "acknowledged" : true, "insertedId" : ObjectId("5ea421fa04263e90dac943fa") } > db.demo677.insertOne({Value:20}); { "acknowledged" : true, ... Read More
AmitDiwan
223 Views
For group query, use MongoDB $group and get the count with $sum. Let us create a collection with documents −> db.demo676.insertOne({"Marks":87}); { "acknowledged" : true, "insertedId" : ObjectId("5ea41eed04263e90dac943f2") } > db.demo676.insertOne({"Marks":75}); { "acknowledged" : true, "insertedId" : ObjectId("5ea41ef304263e90dac943f3") } > db.demo676.insertOne({"Marks":87}); { "acknowledged" : true, ... Read More
AmitDiwan
171 Views
Let us create a collection with documents −> db.demo675.insertOne({ ... "ListOfNames":["John", "Chris", "David"]}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3f5b404263e90dac943ef") } > db.demo675.insertOne({ "ListOfNames":["Bob", "Johnson", "Sam"]}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3f5c804263e90dac943f0") } > db.demo675.insertOne({ "ListOfNames":["Jace", "Sam"]}); { "acknowledged" : true, "insertedId" : ... Read More
AmitDiwan
223 Views
The $or operator performs a logical OR operation on an array of two or more expressions. Let us create a collection with documents −> db.demo674.insertOne({Name:"Chris", Age:21}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3f33604263e90dac943eb") } > db.demo674.insertOne({Name:"David", Age:23}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3f33c04263e90dac943ec") } > ... Read More
AmitDiwan
124 Views
Use max field in order to limit the number of documents in the collection. Following is the query to use the max field in the capped collection −> db.createCollection("demo673", { capped : true, size : 100, max :50 } ) { "ok" : 1 }Let us create a collection with ... Read More
AmitDiwan
242 Views
To fetch a specific document, use dot notation in MongoDB find(). Let us create a collection with documents −> db.demo672.insertOne({Brand:[{CategoryName:"Mobile", "Name":"Oppo"}]}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3ea9b04263e90dac943e5") } > db.demo672.insertOne({Brand:[{CategoryName:"Mobile", "Name":"Samsung"}]}); { "acknowledged" : true, "insertedId" : ObjectId("5ea3eaa404263e90dac943e6") } > db.demo672.insertOne({Brand:[{CategoryName:"Mobile", "Name":"OnePlus"}]}); { "acknowledged" ... Read More
AmitDiwan
717 Views
To get fields from multiple sub-documents, use MongoDB aggregate with $unwind. Let us create a collection with documents −> db.demo671.insertOne( ... { ... ... "details" : [ ... { ... "id" : "1" ... }, ... { ... CountryName:"US", ... ... Read More