In the CITY_TEMPERATURE example, which inner field stores the temperature value for each date?

• A. date
• B. value
• C. city
• D. temp

Answer: (B)

When working with nested data, the actual measurement is stored in a field that represents the value being observed. In the CITY_TEMPERATURE example, each inner object for a date includes metadata like date and city, plus a field that holds the numeric temperature reading. That field is named value, so it stores the temperature value for each date. For example, an inner object would look like { "date": "...", "city": "...", "value": 72 }, where 72 is the temperature. The other fields identify when and where the observation was made, not the measurement itself.