MongoDB CRUD Operations

db.users.insertOne({ name: 'John', age: 25 }); # insert one document
db.users.insertMany([
    { name: 'John', age: 25 },
    { name: 'Jane', age: 30 }
]); # insert multiple documents

db.users.find(); # find all documents
db.users.findOne({ name: 'John' }); # find one document
db.users.find({ age: { $gt: 18 } }); # find with condition

db.users.updateOne(
    { name: 'John' },
    { $set: { age: 26 } }
); # update one document
db.users.updateMany(
    { country: 'USA' },
    { $set: { active: true } }
); # update multiple documents

db.users.deleteOne({ name: 'John' }); # delete one document
db.users.deleteMany({ age: { $lt: 18 } }); # delete multiple documents

db.users.replaceOne(
    { name: 'John' },
    { name: 'John', age: 30, city: 'NYC' }
); # replace entire document