13.4. Filtering Blended Data Sources

Filtering Blended Data

When working with blended data sources in Looker Studio, it's important to understand how filters work with them. Filters are applied to individual data sources first and then to the blended data.

Here's a summary of the key points:

When you apply a filter to a blended data source, the filter is applied to the raw tables (data sources) that are part of the blend.
The filtered results of the individual data sources are then combined according to the blend configuration.
If you have multiple data sources in a blend, filters may affect some data sources but not others, depending on the fields used in the filter.

Example

Let's consider an example with two data sources: Google Analytics and Google Sheets. You have a control for each data source based on the "Country" field. You also have a blended data source created by joining the two data sources on the "Country" field.

When you filter by "Country" for the Google Analytics data source, the following happens:

The filter is applied to the Google Analytics data source, showing only the selected country.
The blended data source is updated to reflect the filtered Google Analytics data.
The filtered Google Analytics data is joined with the Google Sheets data source based on the "Country" field.

When you filter by "Country" for the Google Sheets data source, the following happens:

The filter is applied to the Google Sheets data source, showing only the selected country.
The blended data source is updated to reflect the filtered Google Sheets data.
The filtered Google Sheets data is joined with the unfiltered Google Analytics data source based on the "Country" field.

In both cases, the filters are applied to the individual data sources first, and then the blended data source is updated accordingly.

When working with blended data sources, remember that filters are applied to each data source first and then to the blended data. This can impact your results, so it's essential to understand how the filters are affecting each data source in the blend.