这个教程讲述了如何在 MongoDB 数据库中插入数据，并使用内嵌的 shell 查询数据

一、Switch Database

  1. db
  • db显示当前的数据库
  1. use examples
  • use <db>切换数据库

二、Populate a Collection (Insert)

  1. db.movies.insertMany([
  2.    {
  3.       title: 'Titanic',
  4.       year: 1997,
  5.       genres: [ 'Drama', 'Romance' ],
  6.       rated: 'PG-13',
  7.       languages: [ 'English', 'French', 'German', 'Swedish', 'Italian', 'Russian' ],
  8.       released: ISODate("1997-12-19T00:00:00.000Z"),
  9.       awards: {
  10.          wins: 127,
  11.          nominations: 63,
  12.          text: 'Won 11 Oscars. Another 116 wins & 63 nominations.'
  13.       },
  14.       cast: [ 'Leonardo DiCaprio', 'Kate Winslet', 'Billy Zane', 'Kathy Bates' ],
  15.       directors: [ 'James Cameron' ]
  16.    },
  17.    {
  18.       title: 'The Dark Knight',
  19.       year: 2008,
  20.       genres: [ 'Action', 'Crime', 'Drama' ],
  21.       rated: 'PG-13',
  22.       languages: [ 'English', 'Mandarin' ],
  23.       released: ISODate("2008-07-18T00:00:00.000Z"),
  24.       awards: {
  25.          wins: 144,
  26.          nominations: 106,
  27.          text: 'Won 2 Oscars. Another 142 wins & 106 nominations.'
  28.       },
  29.       cast: [ 'Christian Bale', 'Heath Ledger', 'Aaron Eckhart', 'Michael Caine' ],
  30.       directors: [ 'Christopher Nolan' ]
  31.    },
  32.    {
  33.       title: 'Spirited Away',
  34.       year: 2001,
  35.       genres: [ 'Animation', 'Adventure', 'Family' ],
  36.       rated: 'PG',
  37.       languages: [ 'Japanese' ],
  38.       released: ISODate("2003-03-28T00:00:00.000Z"),
  39.       awards: {
  40.          wins: 52,
  41.          nominations: 22,
  42.          text: 'Won 1 Oscar. Another 51 wins & 22 nominations.'
  43.       },
  44.       cast: [ 'Rumi Hiiragi', 'Miyu Irino', 'Mari Natsuki', 'Takashi Naitè' ],
  45.       directors: [ 'Hayao Miyazaki' ]
  46.    },
  47.    {
  48.       title: 'Casablanca',
  49.       genres: [ 'Drama', 'Romance', 'War' ],
  50.       rated: 'PG',
  51.       cast: [ 'Humphrey Bogart', 'Ingrid Bergman', 'Paul Henreid', 'Claude Rains' ],
  52.       languages: [ 'English', 'French', 'German', 'Italian' ],
  53.       released: ISODate("1943-01-23T00:00:00.000Z"),
  54.       directors: [ 'Michael Curtiz' ],
  55.       awards: {
  56.          wins: 9,
  57.          nominations: 6,
  58.          text: 'Won 3 Oscars. Another 6 wins & 6 nominations.'
  59.       },
  60.       lastupdated: '2015-09-04 00:22:54.600000000',
  61.       year: 1942
  62.    }
  63. ])
  • mongoDB 在 collections 中存储 documents
  • collections 与关系型数据库中的 tables 很像
  • 如果 collection 不存在，mongoDB 在你首次在 collection 存储数据的时候自动创建
  • db.collection.insertMany()插入新 documents 到 moviescollection
  • 上面命令执行完后，会返回一个 document，包含一个 acknowledgement indicator 以及一个数组，该数组包含每个成功插入的 documents 的 id

三、Find All Documents

  1. db.movies.find({})
  • db.collection.find()可以从一个 collection 选择全部的 documents

四、Filter Data with Comparision Operators

在查询过滤文档中指定<field>: <value>

  1. db.movies.find( { "directors": "Christopher Nolan" } );

  • 过滤查询电影的导演为 Christopher Nolan

    1. db.movies.find( { "released": { $lt: ISODate("2000-01-01") } } );

  • 过滤查询电影的发型日期在 2000 年之前

    1. db.movies.find( { "awards.wins": { $gt: 100 } } );

  • 过滤查询电影获奖超过 100 个

    1. db.movies.find( { "languages": { $in: [ "Japanese", "Mandarin" ] } } )

  • 过滤查询电影的语言有 Japanese 和 Mandarin

五、Specify Fields to Return (Projection)

  1. db.movies.find( { }, { "title": 1, "directors": 1, "year": 1 } );
  2. db.movies.find( { }, { "_id": 0, "title": 1, "genres": 1 } );
  • <field>: 1返回的 documents 包含该字段
  • <field>: 0返回的 documents 不包含该字段
  • _id字段默认包含，其他字段默认不包含

六、Aggregate Data ($group)

  1. db.movies.aggregate( [
  2.    { $unwind: "$genres" },
  3.    {
  4.      $group: {
  5.        _id: "$genres",
  6.        genreCount: { $count: { } }
  7.      }
  8.    },
  9.    { $sort: { "genreCount": -1 } }
  10. ] )

七、参考文档