UNIQUE COUNT

The unique count aggregation type counts only the unique values of a specified event property.

UNIQUE COUNT calculation method

UNIQUE COUNT billable metric

Dashboard

Here is how you can create a unique count aggregation from the UI:

1. Access the “Billable metrics” section via the side menu;
2. Create a new billable metric;
3. Define a name, a code and an optional description;
4. Select “count unique” as the aggregation type;
5. Define it this metric is metered or recurring;
6. Define the property to aggregate;
7. Apply dimension groups if any; and
8. Click “Add billable metric”.

This billable metric can be both metered or recurring.

API

    LAGO_URL="https://api.getlago.com"
    API_KEY="__YOUR_API_KEY__"

    curl --location --request POST "$LAGO_URL/api/v1/billable_metrics" \
    --header "Authorization: Bearer $API_KEY" \
    --header 'Content-Type: application/json' \
    --data-raw '{
        "billable_metric": {
        "name": "API Request",
        "code": "api_requests",
        "description": "Number of API requests.",
        "aggregation_type": "unique_count_agg",
        "field_name": "request_id",
        "group": {}
    }
}'

Calculation example

Lago calculates the COUNT_DISTINCT(events.properties.property_name) for the two following events received.

//Event received #1
{
    "transaction_id": "transaction_1",
    "external_customer_id": "1",
    "timestamp": "2022-03-16T00:00:00Z",
    "code": "api_requests",
    "properties": {
        "request_id": "id_1"
    }
}

//Event received #2
{
    "transaction_id": "transaction_2",
    "external_customer_id": "1",
    "timestamp": "2022-03-17T00:00:00Z",
    "code": "api_requests",
    "properties": {
        "request_id": "id_1"
    }
}

In that case, with this aggregation type, Lago only counts the unique values request_id property in the event payloads, resulting in a billable value of 1 unit.