Getting basic values

DQL uses location path syntax to extract values from JSON structures. The following examples demonstrate several examples of getting basic values from JSON data.

Contents

• Example JSON
• Get a top-level field
• Get a nested field
• Get an entire object
• Select a specific index in an array
• Select an entire array
• Return one field of every object in an array
• Return fields that contain special characters in the key name
• Get the number of elements in the list

Example JSON

The examples below use this JSON data:

{
    "name": "John Smith",
    "address": {
        "street": "123 Park Avenue",
        "city": "Atlanta",
        "state": "GA",
        "zip": "12345"
    },
    "phones": [
        {
            "type": "Home",
            "number": "123-456-7890"
        },
        {
            "type": "Cell",
            "number": "098-765-4321"
        }
    ],
    "display name": "myuser123"
}

Get a top-level field

To access a top-level field with DQL, enter the field's name.

DQL

 name

Result

"John Smith"

Get a nested field

To access fields below the top level, use field names separated by dot . delimiters.

DQL

 address.city

Result

"Atlanta"

Get an entire object

Enter the name of an object in the JSON file to retrieve all the data within that object.

DQL

 address

Result

{
    street: '123 Park Avenue',
    city: 'Atlanta',
    state: 'GA',
    zip: '12345',
}

Select a specific index in an array

To access individual values in an array in a JSON file, specify an index number between square brackets after the array's name.

DQL

 phones[0].number

Result

"123-456-7890"

Select an entire array

Enter the name of an array in the JSON file to retrieve all the data within that array.

DQL

 phones

Result

[
    {
        "type": "Home",
        "number": "123-456-7890"
    },
    {
        "type": "Cell",
        "number": "098-765-4321"
    }
]

Return one field of every object in an array

To return a specific field from multiple objects in an array, enter the array's name then the field's name, separated by a dot.

DQL

phones.number

Result

["123-456-7890","098-765-4321"]

Return fields that contain special characters in an array

If a field in the JSON file contains special characters (like spaces), put the field's name in single quotes.

DQL

'display name'

Result

myuser123

Get the number of elements in the list

DQL

$count(phones)

Result

2