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Practice

Deep Dive into JSON Data Format

When fine-tuning text generation AI developed by the OpenAI platform, the training data should be provided in JSON format.

In this lesson, we will take a closer look at the JSON data format.


Structure of JSON​

1. Object​

An object is enclosed with curly braces { } and consists of multiple key-value pairs.

Keys and values are separated by a colon :, and each key-value pair is separated by a comma ,.

JSON Object Example
{
    "key1": "value1",
    "key2": "value2"
}

Keys are always strings enclosed in double quotes " ", and values can be strings, numbers, objects, arrays, or any other supported data types.

JSON Object Example
{
    "name": "John Doe",
    "age": 30,
    "occupation": "developer"
}

In the JSON above:

  • name, age, occupation are keys, and John Doe, 30, developer are their values, respectively.

  • The value of the key name is the string "John Doe", and the value for key age is the number 30.


2. Array​

An array is enclosed in square brackets [ ] and contains a list of values. Each value is separated by a comma. Arrays can include objects, strings, numbers, and other data types.

JSON Array Example
[
    "apple",
    "cherry",
    {
      "product": "banana",
      "price": 1000
    }
]

In the JSON above, the array includes the strings "apple", "cherry", and an object {"product": "banana", "price": 1000} as its three values. Thus, arrays can include various data types.


3. Nested Structure​

JSON can have nested structures containing objects within objects or arrays.

Nested JSON Example
{
    "name": "John Doe",
    "contact": {
        // Nested object within the object
        "email": "john@example.com",
        "phone": "555-1234"
    },
    "hobbies": ["reading", "soccer", "cooking"]
}

JSON Data Types​

JSON supports a variety of data types including strings, numbers, booleans, null, arrays, and objects.

1. String​

A string is a collection of characters enclosed in double quotes " ".

String Example
{
    "string": "Hello"
}

2. Number​

Numbers can be represented in both decimal and integer forms.

Number Example
{
    "integer": 123,
    "decimal": 3.14
}

3. Boolean​

A Boolean type can only have two values: true or false.

Boolean Example
{
    "trueValue": true,
    "falseValue": false
}

4. Null​

Null represents the special value null indicating the absence of a value. For instance, when you don't know someone's phone number, you can set the value to null.

Null Example
{
    "phone": null
}

5. Array​

An array contains multiple values in an ordered list.

Array Example
{
    "fruits": ["apple", "banana", "cherry"]
}

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