$compute

Calculate on specific attributes (e.g., Employee/salary/?$compute=sum) or in the case of an Object attribute (e.g., Employee/objectAtt.property1/?$compute=sum)

Description

This parameter allows you to do calculations on your data.

If you want to perform a calculation on an attribute, you write the following:

GET /rest/Employee/salary/?$compute=$all

If you want to pass an Object attribute, you must pass one of its property. For example:

GET /rest/Employee/objectAtt.property1/?$compute=$all

You can use any of the following keywords:

Keyword	Description
$all	A JSON object that defines all the functions for the attribute (average, count, min, max, and sum for attributes of type Number and count, min, and max for attributes of type String
average	Get the average on a numerical attribute
count	Get the total number in the collection or dataclass (in both cases you must specify an attribute)
min	Get the minimum value on a numerical attribute or the lowest value in an attribute of type String
max	Get the maximum value on a numerical attribute or the highest value in an attribute of type String
sum	Get the sum on a numerical attribute

Example

If you want to get all the computations for an attribute of type Number, you can write:

GET /rest/Employee/salary/?$compute=$all

Response:

{
    "salary": {
        "count": 4,
        "sum": 335000,
        "average": 83750,
        "min": 70000,
        "max": 99000
    }
}

If you want to get all the computations for an attribute of type String, you can write:

GET /rest/Employee/firstName/?$compute=$all

Response:

{
    "salary": {
        "count": 4,
        "min": Anne,
        "max": Victor
    }
}

If you want to just get one calculation on an attribute, you can write the following:

GET /rest/Employee/salary/?$compute=sum

Response:

235000

If you want to perform a calculation on an Object attribute, you can write the following:

GET /rest/Employee/objectAttribute.property1/?$compute=sum

Response:

45