An API call is every time the connector needs to call the data source’s API for information.
In Data Studio this occurs every time you add or change a dashboard with new metrics, dimensions, controls… Equally, when you refresh it, it will count 1 API call for each graph, control or data table you have. Also, if you share the dashboard with your clients, every time they refresh the data or change an option in a control, it will consume API calls.
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