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
Is it possible to cast in a MongoDB Query?
Yes, it is possible to cast in a MongoDB query −
db.yourCollectionName.find("this.yourFieldName >yourValue);To understand the concept, let us create a collection with the document. The query to create a collection with a document is as follows −
> db.castingDemo.insertOne({"Amount":"200"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947e874cf1f7a64fa4df42")
}
> db.castingDemo.insertOne({"Amount":"100"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947e8e4cf1f7a64fa4df43")
}
> db.castingDemo.insertOne({"Amount":"110"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947e944cf1f7a64fa4df44")
}
> db.castingDemo.insertOne({"Amount":"95"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947e9d4cf1f7a64fa4df45")
}
> db.castingDemo.insertOne({"Amount":"85"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947ea44cf1f7a64fa4df46")
}
> db.castingDemo.insertOne({"Amount":"75"});
{
"acknowledged" : true,
"insertedId" : ObjectId("5c947ebd4cf1f7a64fa4df47")
}Display all documents from a collection with the help of find() method. The query is as follows −
> db.castingDemo.find().pretty();
The following is the output −
{ "_id" : ObjectId("5c947e874cf1f7a64fa4df42"), "Amount" : "200" }
{ "_id" : ObjectId("5c947e8e4cf1f7a64fa4df43"), "Amount" : "100" }
{ "_id" : ObjectId("5c947e944cf1f7a64fa4df44"), "Amount" : "110" }
{ "_id" : ObjectId("5c947e9d4cf1f7a64fa4df45"), "Amount" : "95" }
{ "_id" : ObjectId("5c947ea44cf1f7a64fa4df46"), "Amount" : "85" }
{ "_id" : ObjectId("5c947ebd4cf1f7a64fa4df47"), "Amount" : "75" }Here is the query that automatically converts from string to number −
> db.castingDemo.find("this.Amount > 85");The following is the output −
{ "_id" : ObjectId("5c947e874cf1f7a64fa4df42"), "Amount" : "200" }
{ "_id" : ObjectId("5c947e8e4cf1f7a64fa4df43"), "Amount" : "100" }
{ "_id" : ObjectId("5c947e944cf1f7a64fa4df44"), "Amount" : "110" }
{ "_id" : ObjectId("5c947e9d4cf1f7a64fa4df45"), "Amount" : "95" }
Updated on: 30-Jul-2019
216 Views
Advertisements