
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Limit Fields and Slice Projection Together in MongoDB
Use the $slice operator. Let us first create a collection with documents −
> db.limitAndSliceProjectionDemo.insertOne( { "_id" : 101, "UserName" : "Carol", "UserAge" : 26, "UserMesssage" : [ "Hi", "Hello", "Bye", "Awesome", "Good", "Bad", "Nice", "Good Night", "Good Morning" ] } ); { "acknowledged" : true, "insertedId" : 101 }
Following is the query to display all documents from a collection with the help of find() method −
> db.limitAndSliceProjectionDemo.find().pretty();
This will produce the following output −
{ "_id" : 101, "UserName" : "Carol", "UserAge" : 26, "UserMesssage" : [ "Hi", "Hello", "Bye", "Awesome", "Good", "Bad", "Nice", "Good Night", "Good Morning" ] }
Following is the query to limit fields and perform slice projection together. Here, we are slicing from 2 to 4 −
> db.limitAndSliceProjectionDemo.find({ "UserName" : "Carol" }, {"_id": 0, "UserName":0,"UserAge":0, "UserMesssage": { "$slice": [2,4] } }).pretty();
This will produce the following output −
{ "UserMesssage" : [ "Bye", "Awesome", "Good", "Bad" ] }
Advertisements