The add-in can return JSON structures as column values. The add-in enables you to use standard SQL functions to work with these JSON structures. The examples in this section use the following array:
[
{ "grade": "A", "score": 2 },
{ "grade": "A", "score": 6 },
{ "grade": "A", "score": 10 },
{ "grade": "A", "score": 9 },
{ "grade": "B", "score": 14 }
]
JSON_EXTRACT
The JSON_EXTRACT function can extract individual values from a JSON object. The following query returns the values shown below based on the JSON path passed as the second argument to the function:
SELECT Name, JSON_EXTRACT(grades,'[0].grade') AS Grade, JSON_EXTRACT(grades,'[0].score') AS Score FROM Students;
| |
Column Name | Example Value |
Grade | A |
Score | 2 |
JSON_COUNT
The JSON_COUNT function returns the number of elements in a JSON array within a JSON object. The following query returns the number of elements specified by the JSON path passed as the second argument to the function:
SELECT Name, JSON_COUNT(grades,'[x]') AS NumberOfGrades FROM Students;
| |
Column Name | Example Value |
NumberOfGrades | 5 |
JSON_SUM
The JSON_SUM function returns the sum of the numeric values of a JSON array within a JSON object. The following query returns the total of the values specified by the JSON path passed as the second argument to the function:
SELECT Name, JSON_SUM(score,'[x].score') AS TotalScore FROM Students;
| |
Column Name | Example Value |
TotalScore | 41 |
JSON_MIN
The JSON_MIN function returns the lowest numeric value of a JSON array within a JSON object. The following query returns the minimum value specified by the JSON path passed as the second argument to the function:
SELECT Name, JSON_MIN(score,'[x].score') AS LowestScore FROM Students;
| |
Column Name | Example Value |
LowestScore | 2 |
JSON_MAX
The JSON_MAX function returns the highest numeric value of a JSON array within a JSON object. The following query returns the maximum value specified by the JSON path passed as the second argument to the function:
SELECT Name, JSON_MAX(score,'[x].score') AS HighestScore FROM Students;
| |
Column Name | Example Value |
HighestScore | 14 |
DOCUMENT
The DOCUMENT function can be used to retrieve the entire document as a JSON string. See the following query and its result as an example:
SELECT DOCUMENT(*) FROM Customers;
The query above will return the entire document as shown.
{ "id": 12, "name": "Lohia Manufacturers Inc.", "address": { "street": "Main Street", "city": "Chapel Hill", "state": "NC"}, "offices": [ "Chapel Hill", "London", "New York" ], "annual_revenue": 35,600,000 }