[MongoDB] Model Relationships Between Documents (1)

// student document
{
	_id : 'ohnamju_01',
	name : 'ohnamju'
}

// account document
{
	account_id : 'ohnamju_01',
	balance : 0,
}

/* 자주 account 정보에서 name이 필요하다면, */
{
	_id : 'ohnamju_01',
	name : 'ohnamju'
	balance: 0
}

- 문제점 : 필요하지 않은 데이터도 load 시켜 read를 수행할 때 느려질 수 있음.

the most frequently-accessed portion of the data should go in the collection that the application loads first.

제일 중요한 점은 우리 어플리케이션이 어떻게 데이터를 사용하는지에 초점을 맞춰서 설계하는 것

예시) movie 와 movie detail로 나누자

// movie collection
{
	"id" : 1,
	"title" : "The Arrival of a Train",
	"year" : 1895,
	"runtime" : 1,
	"released" : IsoDate("1895-01-25")
	"type": "movie",
 	"directors": [ "Auguste Lumière", "Louis Lumière" ],
	"countries": [ "France" ],
	"genres": [ "Documentary", "Short" ],
}

// movie_details collection
{
  "_id": 156,
  "movie_id": 1, // reference to the movie collection
  "poster": "http://ia.media-imdb.com/images/M/MV5BMjEyNDk5MDYzOV5BMl5BanBnXkFtZTgwNjIxMTEwMzE@._V1_SX300.jpg",
  "plot": "A group of people are standing in a straight line along the platform of a railway station, waiting for a train, which is seen coming at some distance. When the train stops at the platform, ...",
  "fullplot": "A group of people are standing in a straight line along the platform of a railway station, waiting for a train, which is seen coming at some distance. When the train stops at the platform, the line dissolves. The doors of the railway-cars open, and people on the platform help passengers to get off.",
  "lastupdated": ISODate("2015-08-15T10:06:53"),
  "imdb": {
    "rating": 7.3,
    "votes": 5043,
    "id": 12
  },
  "tomatoes": {
    "viewer": {
      "rating": 3.7,
      "numReviews": 59
    },
    "lastUpdated": ISODate("2020-01-29T00:02:53")
  }
}