- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Found 1349 Articles for MongoDB
1K+ Views
To create views in MongoDB, use createView(). Let us create a collection with documents −> db.demo113.insertOne( ... { _id: 1, StudentId: "101", "Details": { Name: "Chris", Age: 21 }, Subject: "MySQL" } ... ); { "acknowledged" : true, "insertedId" : 1 }Display all documents from a collection with the help of find() method −> db.demo113.find().pretty();This will produce the following output −{ "_id" : 1, "StudentId" : "101", "Details" : { "Name" : "Chris", "Age" : 21 }, "Subject" : "MySQL" }Following is the query to create views in MongoDB ... Read More
224 Views
To update, you need to use update() for the field whose collection is set with capped: true. Let us create a collection with documents −> db.createCollection("Demo112", { capped : true, size : 14, max : 3 } ); { "ok" : 1 } > db.demo112.insertOne({"Name":"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ef47a9fd5fd66da21447e") } > db.demo112.insertOne({"Name":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ef47e9fd5fd66da21447f") } > db.demo112.insertOne({"Name":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ef4919fd5fd66da214480") }Display all documents from a collection with the help of find() method −> db.demo112.find();This will produce the following output −{ "_id" : ... Read More
300 Views
For this, use aggregate() in MongoDB. In that, use $slice to slice array inside array. Let us create a collection with documents −> db.demo111.insertOne( ... { ... "_id" : 101, ... "Name" : "Chris", ... "Details" : [ ... { ... "_id" : 101, ... "Score" : 78, ... "Subjects" : [ ... { ... ... Read More
136 Views
To update data in MongoDB, use update(). Let us create a collection with documents −> db.demo110.insertOne({"Name":"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2eeb949fd5fd66da21447b") } > db.demo110.insertOne({"Name":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2eeb9f9fd5fd66da21447c") } > db.demo110.insertOne({"Name":"Bob"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2eeba39fd5fd66da21447d") }Display all documents from a collection with the help of find() method −> db.demo110.find();This will produce the following output −{ "_id" : ObjectId("5e2eeb949fd5fd66da21447b"), "Name" : "Chris" } { "_id" : ObjectId("5e2eeb9f9fd5fd66da21447c"), "Name" : "David" } { "_id" : ObjectId("5e2eeba39fd5fd66da21447d"), "Name" : "Bob" }Following is the query to update data in MongoDB ... Read More
757 Views
To get the data of the nested JSON object in MongoDB, use findOne(). Let us create a collection with documents −> db.demo109.insertOne( ... { ... "Name" : "Chris", ... "Subjects" : [ ... { ... "Id" : "100", ... "Name":"MySQL", ... "InstructorDetails" : [ ... { ... "Name" : "John" ... ... Read More
664 Views
To remove duplicate entries by two keys, use aggregate() in MongoDB. Let us create a collection with documents −> db.demo108.insertOne({"Value1":23, "Value2":24}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee3e49fd5fd66da214477") } > db.demo108.insertOne({"Value1":23, "Value2":25}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee3f29fd5fd66da214478") } > db.demo108.insertOne({"Value1":23, "Value2":24}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee3f59fd5fd66da214479") }Display all documents from a collection with the help of find() method −> db.demo108.find();This will produce the following output −{ "_id" : ObjectId("5e2ee3e49fd5fd66da214477"), "Value1" : 23, "Value2" : 24 } { "_id" : ObjectId("5e2ee3f29fd5fd66da214478"), "Value1" : 23, "Value2" : 25 } { "_id" : ... Read More
3K+ Views
To use variables, work with var in MongoDB. Let us create a collection with documents −> db.demo107.insertOne({"Name":"Chris"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee1b19fd5fd66da214471") } > db.demo107.insertOne({"Name":"Bob"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee1b49fd5fd66da214472") } > db.demo107.insertOne({"Name":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5e2ee1b89fd5fd66da214473") }Display all documents from a collection with the help of find() method −> db.demo107.find();This will produce the following output −{ "_id" : ObjectId("5e2ee1b19fd5fd66da214471"), "Name" : "Chris" } { "_id" : ObjectId("5e2ee1b49fd5fd66da214472"), "Name" : "Bob" } { "_id" : ObjectId("5e2ee1b89fd5fd66da214473"), "Name" : "David" }Following is the query to use variable in ... Read More
207 Views
You can use bulkWrite(). Let us create a collection with documents −> db.demo105.insertOne( { _id:'101', Name:'Chris', Details:[{ Marks1:60, Marks2:70, Marks3:70 }, { Marks1:70, Marks2:70, Marks3:90 }] } ); { "acknowledged" : true, "insertedId" : "101" }Display all documents from a collection with the help of find() method −> db.demo105.find().pretty();This will produce the following output −{ "_id" : "101", "Name" : "Chris", "Details" : [ { "Marks1" : 60, "Marks2" : 70, "Marks3" : 70 }, { ... Read More
200 Views
To implement $dateToString on array items, use aggregate() in MongoDB. Let us create a collection with documents −> db.demo104.insertOne( ... { ... ... "AppName" : "Online Book", ... "Details" : [ ... { ... "ClientName" : "Chris", ... "Deadline" : new ISODate("2020-03-10") ... } ... ] ... } ... ); { "acknowledged" : true, "insertedId" : ObjectId("5e2ed7fd9fd5fd66da21446f") }Display all documents from a collection with the help of ... Read More
726 Views
To query on the last object of an array, use aggregate(). Let us create a collection with documents −> db.demo103.insertOne( { "Details" : [ { "StudentId" : 101, "Details" : "MongoDB" }, {"StudentId" : 102, "Details" : "MySQL" }, { "StudentId" : 103, "Details" : "Java" } ], "Details1" : [ { "StudentId" : 104, "Number" : 3 } ] } ); { "acknowledged" : true, "insertedId" : ObjectId("5e2ed2dd9fd5fd66da21446e") }Display all documents from a collection with the help of find() method −> db.demo103.find();This will produce the following output −{ "_id" : ObjectId("5e2ed2dd9fd5fd66da21446e"), "Details" : ... Read More