How to search in array of object in mongodb

Question

The right way is:

db.users.find({awards: {$elemMatch: {award:'National Medal', year:1975}}})

$elemMatch allows you to match more than one component within the same array element.

Without $elemMatch mongo will look for users with National Medal in some year and some award in the year 1975, but not for users with National Medal in 1975.

See MongoDB $elemMatch Documentation for more info. See Read Operations Documentation for more information about querying documents with arrays.

Use $elemMatch to find the array of a particular object

db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})

as explained in above answers Also, to return only one field from the entire array you can use projection into find. and use $

db.getCollection("sizer").find(
  { awards: { $elemMatch: { award: "National Medal", year: 1975 } } },
  { "awards.$": 1, name: 1 }
);

will be return

{
    _id: 1,
    name: {
        first: 'John',
        last: 'Backus'
    },
    awards: [
        {
            award: 'National Medal',
            year: 1975,
            by: 'NSF'
        }
    ]
}

You can do this in two ways:

1. ElementMatch - $elemMatch (as explained in above answers)

   db.users.find({ awards: { $elemMatch: {award:'Turing Award', year:1977} } })

2. Use $and with find

   db.getCollection('users').find({"$and":[{"awards.award":"Turing Award"},{"awards.year":1977}]})