• [MongoDB] Introduce to MongoDB


    1. Use or create a database:

    use wandRecorder

    You will use keyword to create or fetch a exicting database.

    2. Find all documents in the database.

    db.wands.find()

    You already start with db keywrod. Then follow your collection name, here is 'wands', find() method will return all the documents in that collection.

    3. insert document to the collections:

    db.wands.insert({name: 'Dream Bender', creator: 'Foxmond'})

    Use insert() metod to insert json data to the collection as a document.

    4. Find a value in the collections:

    db.wands.find({name: 'Storm Seeker'})

    You can pass the json object or Bson object into the find method.

    http://bsonspec.org/

    Result:

    {
      "_id": ObjectId('d0a77e57a0544ec7ad5a740b'),
      "name": "Storm Seeker",
      "creator": "Olivemist",
      "level_required": 96,
      "price": 55.99,
      "powers": [
        "Wind",
        "Static"
      ],
      "damage": {
        "magic": 2,
        "melee": 5
      }
    }

    5. The data type not necessary to be array, number or string, they canbe Object, Date also:

    db.wands.insert({
      "name": "Dream Bender",
      "creator": "Foxmond",
      "level_required": 10,
      "price": 34.9,
      "powers": ["Fire","Love"],
      "damage": {"magic": 4, "melee": 2}
    });

    6. Find value in a array:

    db.wands.find({powers: 'Fire'})
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  • 原文地址:https://www.cnblogs.com/Answer1215/p/4967833.html
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