Looker Studio issue with Data Control (GA4)

[jlane]

I've noticed an issue when using the Data Control for GA4 data. If I have two properties, each with the same Custom Dimensions, when I switch properties with the data control, the data in the grid for that custom dimension becomes data for a totally different dimension.

Example:

Report has a table with Custom Dimension 1 and event count metric. The data control is set to Property A.

I set data control to Property B, which also has Custom Dimension 1.

The table, which should continue to show Custom Dimension 1 and event count metric now shows some completely different Dimension and event count.

My hypothesis is that the Custom Dimensions were not created in the same order in both properties, and so even though they share the same name "Custom Dimension 1", Looker Studio does not treat them as the same.

Anyone on the Looker Studio team know what is going on here?

[a_aleinikov]

Hi @jlane ,

You’re exactly right — Looker Studio relies on the internal index/order of custom dimensions from GA4, not just their display names. So even if both properties have a “Custom Dimension 1,” they may map to different internal fields if they were created in different orders.

Workarounds you can try:

• Use standardized dimension naming and setup across all GA4 properties.

• In Looker Studio, create separate data sources for each property instead of relying only on Data Control.

• Use calculated fields to align dimensions if possible.

It’s a tricky issue, and I recommend submitting feedback through Looker Studio so the team is aware.

[jlane]

If I were to delete all of the CDs in one of the properties and recreate
them in the same order as the other property, would this fix the issue?

--
Jeff Lane
Sr. Manager, Applied Analytics
<PII Removed by Staff>

[阿泰]

Q: So even though they share the same name "Custom Dimension 1", Looker Studio does not treat them as the same.
A: Absolutely! Although they have the same name, they have different "column IDs" in Looker Studio. So you should switch to Property B and re-import the custom dimension.