In Power BI, a gateway is a component that facilitates secure and efficient communication between Power BI services in the cloud and data sources that reside on-premises or in private networks.

It acts as a bridge between Power BI and your organization's data sources, enabling data refresh, query execution, and data movement while maintaining security and data privacy.

Here's more about Power BI Gateways:

Data Source Connectivity

A gateway is primarily used to connect to on-premises data sources such as databases (SQL Server, Oracle, MySQL), files (Excel, CSV), on-premises Analysis Services, and other sources that aren't directly accessible from the Power BI service in the cloud.

Data Refresh

One of the key functions of a gateway is to enable data refresh for reports and dashboards that use on-premises data sources.

The gateway ensures that the data in the cloud is kept up-to-date with changes in your local data sources.

DirectQuery

Gateways also enable DirectQuery mode, which allows you to create reports that run live queries against on-premises data sources.

This can be useful for scenarios where real-time data is required.

Scheduled Refresh

You can configure a gateway to perform scheduled data refresh at specific intervals, ensuring that the cloud-based reports and dashboards reflect the latest data from on-premises sources.

Query Folding

Gateways optimize data refresh by utilizing query folding, which means that as much of the data transformation work as possible is done at the data source, reducing data movement.

Multiple Data Sources

A single gateway can handle connections to multiple data sources within your organization.

Security and Authentication

Gateways ensure that data access is secure by using encryption and allowing you to set up authentication methods, such as Windows authentication or database credentials.

Personal Mode and Enterprise Mode

Power BI offers two types of gateways: Personal Mode and Enterprise Mode.

Personal Mode is suitable for individual users, while Enterprise Mode is designed for organizations with more advanced data sharing needs.

Installation and Configuration

To use a gateway, you need to install it on a machine within your organization's network.

You then configure the gateway with the required data source connections and authentication settings.

Power BI Service Integration

Gateways are managed through the Power BI service. You can monitor gateway status, configure data source credentials, and manage connections.

High Availability

For critical scenarios, you can configure high availability by using multiple gateways in a cluster.

A gateway in Power BI is a crucial component for securely connecting cloud-based Power BI services to on-premises data sources.

It enables data refresh, DirectQuery, and real-time reporting by facilitating communication between cloud and on-premises environments while maintaining data privacy and security.

Want to learn more? Check out my "What Is A...." blog series on common Power BI functionality:

What Is A Measure?

What Is A Slicer?

What Is Power Query?

What Is A Paginated Report?

What Is A Date Hierarchy?