MongoDB and Crud Operations
What is MongoDB?
MongoDB, also known as Mongo, is an open-source document database used in many modern web applications. It is classified as a NoSQL database because it does not rely on a traditional table-based relational database structure.
Instead, Mongo uses JSON-like documents with dynamic schemas. This means that, unlike relational databases, MongoDB does not require a predefined schema before you add data to a database. You can alter the schema at any time and as often as is necessary without having to set up a new database with an updated schema.
MongoDB Crud Operations
Insert /add One Document
db.getCollection('Student').insertOne(
{ "name": "John",
"dateOfBirth": "1990-01-01T00:00:00Z",
"subjects": ["Application frameworks", "Computer architecture"]
})
Inserting/Adding 2 documents to the same collection.
db.getCollection('Student').insertMany([
{ "name": "Smith",
"dateOfBirth": "1990-01-15T00:00:00Z",
"subjects": ["Application frameworks", "Computer architecture"],
"isActive": true
},
{
"name": "Jane",
"dateOfBirth": "1990-02-15T00:00:00Z",
"subjects": ["Application frameworks", "Computer architecture"],
"isActive": false
}
] )
Find the document by ‘name’.
db.getCollection('Student').find({"name":"John"})
Find the document by ‘_id’.
db.getCollection('Student').find({"_id":ObjectId("6043906579f5ccfbfb9649b7")})
Update the Document
Add ‘Distributed Computing’ to the subjects list.
db.getCollection('Student').updateOne(
{
"name":"John"
},
{
$push:{"subjects": "Distributed Computing"}
}
)
Find And Update the Document
Find the document with the name ‘Smith’ and isActive flag is true and add Distributed computing to subjects.
db.getCollection('Student').updateOne(
{
"name":"Smith",
"isActive":true
},
{
$push:{"subjects": "‘Distributed Computing"}
}
)
Update the first document ‘isActive’ to false.
db.getCollection('Student').updateOne(
{
"name": "John"
},
{
$push:{"isActive": false}
}
)
Note
Even Though earlier We doesn't have isActive Document in Object1 "name": "John" after we update it by giving "isActive":false Document will be updated by adding new Document "isActive":false
Removing the document.
db.getCollection('Student').find({})
Excellent Work
ReplyDelete