Note: There is a new version of the personal gateway for Power BI, called the On-premises data gateway (personal mode). The following article describes the previous version of the personal gateway, called Power BI Gateway - Personal, which will be retired and stop working after July 31, 2017. For information about the new version of the personal gateway, including how to install the new version, see the On-premises data gateway (personal mode) article. Fast combine is also available in the new version of the personal gateway, and is described in that article, too.

You may receive the following error based on the privacy settings for your data sources when used with the personal gateway.

An error occurred while processing the data in the dataset.

[Unable to combine data] <query part>/<…>/<…> is accessing data sources that have privacy levels which cannot be used together. Please rebuild this data combination.

To work around this error, you can turn on Fast Combine. Fast Combine will ignore the privacy settings allowing the different data sources to be combined.

Note:

Privacy levels are not considered when combining data. This could expose sensitive or confidential data to another data source when combining data.

What is Fast Combine?

To learn more about privacy levels and Fast Combine, you can look at Privacy Levels. By default, the privacy level will be set to private which could result in the error mentioned above. This is because a setting of private will isolate the data source from other sources. An example of where this would be a problem would be a parameterized query getting inputs from another data source.

Turning Fast Combine on will ignore the private setting and allow the execution to occur.

Turn on Fast Combine

You can use the following steps to enable Fast Combine for your personal gateway. The On-Premises Data Gateway does not have this setting.

  1. Open ConnectorConfig.xml. This may be in one of two locations on your machine. If you are an administrator on the computer, it will be the following.

    C:\Program Files\Power BI Personal Gateway\1.0\Configurator\Connector

    If you are not an administrator, the location will be the following.

    C:\Users\[username]\AppData\Local\Power BI Personal Gateway\1.0\Configurator\Connector
  2. Add the <EnableFastCombine> element with a value of true to the config file. Adding this element will turn Fast Combine on.

    <EnableFastCombine>true</EnableFastCombine>

  3. Exit and re-launch the gateway configuration screen.

  4. You will see a status letting you know that Fast Combine is enabled.

Turn off Fast Combine

  1. Open ConnectorConfig.xml. This may be in one of two locations on your machine. If you are an administrator on the computer, it will be the following.

    C:\Program Files\Power BI Personal Gateway\1.0\Configurator\Connector

    If you are not an administrator, the location will be the following.

    C:\Users\[username]\AppData\Local\Power BI Personal Gateway\1.0\Configurator\Connector
  2. Remove the <EnableFastCombine> element from the config file. Removing this element will turn Fast Combine off.

  3. Exit and re-launch the gateway configuration screen.

  4. You will no longer see a status telling you know that Fast Combine is enabled.

See also

On-premises data gateway (personal mode) - the new version of the personal gateway Privacy Levels
Common query tasks in Power BI Desktop
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