how to find documents in an array mongodb code example
Example 1: find object in array mongodb
db.users.findOne({"_id": id},{awards: {$elemMatch: {award:'Turing Award', year:1977}}})
Example 2: mongodb find array with element
// Finds all documents that have a property named "tags"
// which has at least one array element matching "red"
db.inventory.find( { tags: "red" } )