insert pivot table from power bi dataset: what is refreshed?

Hi, I have Office 365. I inserted Pivot Table from Power BI dataset (on Power BI service) & made a pivot table in Excel.

The Power BI dataset uses a gateway to connect to SQL server & it can pull information from SQL server. It is not set to refresh on a schedule.

When I click on 'Refresh Data' in the pivot table in Excel, what is refreshed? Does it pull the static data from Power BI again, or does the Power BI dataset pull information from SQL server again & the new data is reflected in the Pivot Table?

Thanks for clarifying!