MongoDB Insert, find, update and delete

 abc123> db.eswar.insertOne({SRN:001,SName:'a',yr:3})

{

  acknowledged: true,

  insertedId: ObjectId("66f392b1d8b1cbf0117c527c")

}

abc123> db.eswar.insertOne({SRN:002,SName:'b',yr:3})

{

  acknowledged: true,

  insertedId: ObjectId("66f392cbd8b1cbf0117c527d")

}

abc123> db.eswar.insertOne({SRN:003,SName:'c',yr:2})

{

  acknowledged: true,

  insertedId: ObjectId("66f392e3d8b1cbf0117c527e")

}

abc123> db.eswar.find()

[

  {

    _id: ObjectId("66f392b1d8b1cbf0117c527c"),

    SRN: 1,

    SName: 'a',

    yr: 3

  },

  {

    _id: ObjectId("66f392cbd8b1cbf0117c527d"),

    SRN: 2,

    SName: 'b',

    yr: 3

  },

  {

    _id: ObjectId("66f392e3d8b1cbf0117c527e"),

    SRN: 3,

    SName: 'c',

    yr: 2

  }

]

abc123> show collections

eswar

abc123> db.eswar.update({SName:'C'},{$set:{yr:3}})

DeprecationWarning: Collection.update() is deprecated. Use updateOne, updateMany, or bulkWrite.

{

  acknowledged: true,

  insertedId: null,

  matchedCount: 0,

  modifiedCount: 0,

  upsertedCount: 0

}

abc123> db.eswar.update({SName:'c'},{$set:{yr:3}})

{

  acknowledged: true,

  insertedId: null,

  matchedCount: 1,

  modifiedCount: 1,

  upsertedCount: 0

}

abc123> db.eswar.find()

[

  {

    _id: ObjectId("66f392b1d8b1cbf0117c527c"),

    SRN: 1,

    SName: 'a',

    yr: 3

  },

  {

    _id: ObjectId("66f392cbd8b1cbf0117c527d"),

    SRN: 2,

    SName: 'b',

    yr: 3

  },

  {

    _id: ObjectId("66f392e3d8b1cbf0117c527e"),

    SRN: 3,

    SName: 'c',

    yr: 3

  }

]

abc123> db.eswar.delete({SName:'c'})

TypeError: db.eswar.delete is not a function

abc123> db.eswar.deleteOne({SName:'c'})

{ acknowledged: true, deletedCount: 1 }

abc123> db.eswar.find()

[

  {

    _id: ObjectId("66f392b1d8b1cbf0117c527c"),

    SRN: 1,

    SName: 'a',

    yr: 3

  },

  {

    _id: ObjectId("66f392cbd8b1cbf0117c527d"),

    SRN: 2,

    SName: 'b',

    yr: 3

  }

]

abc123>

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