MongoDB is an open-source, non-relational database management system (DBMS) that uses a flexible document-oriented data model. It stores data in JSON-like documents called BSON (Binary JSON), allowing for dynamic schema design and high scalability.
Install
Commands and Common Operations
# run MongoDB
brew services start mongodb-community@8.0
# stop MongoDB
brew services stop mongodb-community@8.0
# mongo shell
mongosh
# show default database
db
# show all databases
show dbs
# create or select a database
use <db_name>
# show collections
show collections
# insert one element
db.<collection>.insertOne(<JSON>)
# insert multiple elements
db.<collection>.insert(<LIST OF JSONs>)
# getting all documents
db.<collection>.find()
# getting documents
# query or query_selector is a JSON like filter
db.<collection>.find(<query>)
# update one document
df.<collection>.updateOne(<query_selector>, {$set: <JSON>)
# update many documents
df.<collection>.updateMany(<query_selector>, {$set: <JSON>)
# $currentDate operator
df.<collection>.updateOne(<query_selector>, {$set: <JSON>, $currentDate: {lastChanged: true})
# deleting documents
db.<collection>.deleteOne(<query_selector>)
db.<collection>.deleteMany(<query_selector>)Fancier Operations
db.<collection>.find({'parent_key.child_key': true, size: 'M'})
# gt: greater than
db.<collection>.find({'parent_key.child_key': {$gt: 10}})
db.<collection>.find({'parent_key.child_key': {$in: [<value1>, <value2>, <value3>]}})
db.<collection>.find({'parent_key.child_key': {$nin: [<value1>, <value2>, <value3>]}})
# lte: less than or equal
db.<collections>.find({$or: [{'parent_key.child_key': true}, {age: {$lte: 2}}]