Dot notation: reach into substructure

Introduction to MongoDB in Python

Donny Winston

Instructor

A functional density

db.laureates.find_one({
  "firstname": "Walter",
  "surname": "Kohn"})

{'born': '1923-03-09',
 'bornCity': 'Vienna',
 'bornCountry': 'Austria',
 'firstname': 'Walter',
 'prizes': [
  {'affiliations': [
    {'city': 'Santa Barbara, CA',
     'country': 'USA',
     'name': ('University of '
              'California')
    }],
   'category': 'chemistry',
   'motivation': (
    '"for his development of the '
    'density-functional theory"'),
   'share': '2',
   'year': '1998'
  }],
 'surname': 'Kohn',
 ...} # showing partial document

db.laureates.count_documents({
 "prizes.affiliations.name": (
  "University of California")})

db.laureates.count_documents({
 "prizes.affiliations.city": (
  "Berkeley, CA")})

No Country for Naipaul

db.laureates.find_one({'surname': 'Naipaul'})

{'_id': ObjectId('5b9ec791f35b63093c3d98b7'),
 'born': '1932-08-17',
 'died': '2018-08-11',
 'diedCity': 'London',
 'diedCountry': 'United Kingdom',
 'diedCountryCode': 'GB',
 'firstname': 'Sir Vidiadhar Surajprasad',
 'gender': 'male',
 'id': '747',
 'prizes': [{'affiliations': [[]],
   'category': 'literature',
   'motivation': ('"for having united perceptive narrative and '
                  'incorruptible scrutiny in works that compel us '
                  'to see the presence of suppressed histories"'),
   'share': '1',
   'year': '2001'}],
 'surname': 'Naipaul'}

db.laureates.count_documents({"bornCountry": {"$exists": False}})

Multiple prizes

db.laureates.count_documents({})

db.laureates.count_documents({"prizes": {"$exists": True}})

db.laureates.count_documents({"prizes.0": {"$exists": True}})

db.laureates.count_documents({"prizes.1": {"$exists": True}})

Multiple-prize winners

laureates_photos

On to exercises!

Introduction to MongoDB in Python