5

sudo systemctl start mongod

mongosh

use testDB

db.students.insertMany([

  { _id: 1, name: "Alice", age: 22, marks: 85 },

  { _id: 2, name: "Bob", age: 21, marks: 78 },

  { _id: 3, name: "Charlie", age: 23, marks: 92 },

  { _id: 4, name: "David", age: 20, marks: 88 },

  { _id: 5, name: "Eve", age: 22, marks: 76 }

])

db.students.countDocuments({})

db.students.find().sort({ marks: -1 })

db.students.find().sort({ marks: -1 }).limit(3)

db.students.find().sort({ marks: -1 }).skip(2)

db.students.aggregate([

  { $group: { _id: "$age", avgMarks: { $avg: "$marks" } } }

])

db.students.find().pretty()












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