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Found 6705 Articles for Database

211 Views
To get all embedded documents, use $project in MongoDB. Let us create a collection with documents −> db.demo220.insertOne({ ... "id":101, ... "FullName" : "John Doe", ... "EmailId" : "john12@gmail.com", ... "ShippingDate" : new ISODate(), ... "details" : { "_id" :1001, "isMarried" :true } ...} ...); { "acknowledged" : true, "insertedId" : ObjectId("5e3eaf5b03d395bdc213471d") } > db.demo220.insertOne( ...{ ... "id":102, ... "FullName" : "John Smith", ... "EmailId" : "johnsmith@gmail.com", ... "ShippingDate" : new ISODate(), ... "details" : { "_id" :1002, "isMarried" :false } ... } ... ); { "acknowledged" ... Read More

296 Views
To search for a specific domain name, use /i. Let us create a collection with documents −> db.demo219.insertOne({"details":{"WebsiteURL":"www.EXAMPLE.com"}}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e667203d395bdc2134718") } > db.demo219.insertOne({"details":{"WebsiteURL":"www.gmail.com"}}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e667803d395bdc2134719") } > db.demo219.insertOne({"details":{"WebsiteURL":"www.example.com"}}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e667f03d395bdc213471a") }Display all documents from a collection with the help of find() method −> db.demo219.find();This will produce the following output −{ "_id" : ObjectId("5e3e667203d395bdc2134718"), "details" : { "WebsiteURL" : "www.EXAMPLE.com" } } { "_id" : ObjectId("5e3e667803d395bdc2134719"), "details" : { "WebsiteURL" : "www.gmail.com" } } { "_id" : ObjectId("5e3e667f03d395bdc213471a"), "details" : ... Read More

197 Views
The MongoDB aggregation pipeline has stages. Each stage transforms the documents as they pass through the pipeline.Let us first create a collection with documents −> db.demo218.insertOne({"Name":"Chris", "Branch":"CS", Marks:[65, 78, 36, 90]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5f4903d395bdc2134712") } > db.demo218.insertOne({"Name":"David", "Branch":"ME", Marks:[56, 45, 42, 51]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5f6203d395bdc2134713") } > db.demo218.insertOne({"Name":"Chris", "Branch":"CS", Marks:[78, 65, 89]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5f6c03d395bdc2134714") }Display all documents from a collection with the help of find() method −> db.demo218.find();This will produce the following output −{ "_id" : ObjectId("5e3e5f4903d395bdc2134712"), "Name" : "Chris", "Branch" ... Read More

2K+ Views
To trim spaces from field, use $trim in MongoDB. Let us create a collection with documents −> db.demo217.insertOne({"FullName":" Chris Brown"}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5d1e03d395bdc213470f") } > db.demo217.insertOne({"FullName":" David Miller"}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5d2503d395bdc2134710") } > db.demo217.insertOne({"FullName":" John Doe"}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e5d2b03d395bdc2134711") }Display all documents from a collection with the help of find() method −> db.demo217.find();This will produce the following output −{ "_id" : ObjectId("5e3e5d1e03d395bdc213470f"), "FullName" : " Chris Brown" } { "_id" : ObjectId("5e3e5d2503d395bdc2134710"), "FullName" : " David Miller" ... Read More

196 Views
Let us first create a collection with documents −> db.demo216.insertOne({"ClientName":"John", "ClientAge":34}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e351003d395bdc213470c") } > db.demo216.insertOne({"ClientName":"Bob", "ClientAge":32}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e351703d395bdc213470d") } > db.demo216.insertOne({"ClientName":"Mike", "ClientAge":35}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e351c03d395bdc213470e") }Display all documents from a collection with the help of find() method −> db.demo216.find();This will produce the following output −{ "_id" : ObjectId("5e3e351003d395bdc213470c"), "ClientName" : "John", "ClientAge" : 34 } { "_id" : ObjectId("5e3e351703d395bdc213470d"), "ClientName" : "Bob", "ClientAge" : 32 } { "_id" : ObjectId("5e3e351c03d395bdc213470e"), "ClientName" : "Mike", "ClientAge" : 35 }Following is the ... Read More

2K+ Views
Since boolean has two values: true and false, therefore, use true or false keyword in MongoDB. Let us create a collection with documents −> db.demo215.insertOne({"EmployeeDetails":[{EmployeeName:"David", "isMarried":false, "Salary":56000}]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e344003d395bdc2134708") } > db.demo215.insertOne({"EmployeeDetails":[{EmployeeName:"Bob", "isMarried":true, "Salary":60000}]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e344d03d395bdc2134709") } > db.demo215.insertOne({"EmployeeDetails":[{EmployeeName:"Chris", "isMarried":false, "Salary":78000}]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e345a03d395bdc213470a") } > db.demo215.insertOne({"EmployeeDetails":[{EmployeeName:"Mike", "isMarried":true, "Salary":17000}]}); { "acknowledged" : true, "insertedId" : ObjectId("5e3e346f03d395bdc213470b") }Display all documents from a collection with the help of find() method −> db.demo215.find();This will produce the following output −{ "_id" ... Read More

367 Views
To aggregate multiple arrays into a single array, use $project in MongoDB. Let us create a collection with documents −> db.demo119.insertOne( ... { ... "_id": 101, ... "WebDetails": [ ... { ... "ImagePath": "/all/image1", ... "isCorrect": "false" ... }, ... { ... "ImagePath": "/all/image2", ... "isCorrect": "true" ... } ... ... Read More

969 Views
Let us first create a collection with documents −> db.demo118.insertOne( ... { ... "Id" : "101", ... "Name" : "Chris", ... "Subjects" : [ ... "MySQL", ... "MongoDB", ... "Java" ... ], ... "Details" : [ ... { ... "Name" : "David", ... S:"MongoDB" ... }, ... { ... Read More

378 Views
To aggregate sum of values in a list of dictionaries, use $sum along with aggregate(). Let us create a collection with documents −> db.demo117.insertOne( ... { ... ID:101, ... Details:[ ... { ... Name:'Chris', ... Value1:20, ... Value2:30, ... Value3:10 ... }, ... { ... Name:'David', ... ... Read More

112 Views
To find only a single document, use findOne() in MongoDB. Let us create a collection with documents −> db.demo116.insertOne({"EmployeeId":101, "EmployeeName":"John"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2eff98d8f64a552dae635b") } > db.demo116.insertOne({"EmployeeId":102, "EmployeeName":"Bob"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2eff9fd8f64a552dae635c") } > db.demo116.insertOne({"EmployeeId":103, "EmployeeName":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2effa5d8f64a552dae635d") } > db.demo116.insertOne({"EmployeeId":102, "EmployeeName":"Mike"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2effb7d8f64a552dae635e") }Display all documents from a collection with the help of find() method −> db.demo116.find();This will produce the following output −{ "_id" : ObjectId("5e2eff98d8f64a552dae635b"), "EmployeeId" : 101, "EmployeeName" : "John" } { "_id" ... Read More