A cyclic reference was encountered during evaluation in Power BI

When I press refresh button in Power BI (version 2.112.1161.0) I have this error message

! Table1 A cyclic reference was encountered during evaluation. ! Table2 Loading blocked by failures with other queries. 

I always solve it by going to another tab (sheet) and press refresh button and everything's fine. The refresh completes.

Is this error serious? How could I fix it or debug it?

4 Answers

This is a long-standing bug that you can safely ignore. There must be some race condition bug that occasionally causes the PQ engine to fail but as you say, it goes away on its own.

For others reading, this is different to the circular references errors you sometimes get in the vertipaq engine caused by model ambiguity caused by relationships, multiple calculated columns or genuine logical errors and is to do with the PQ engine.

You can go through some definitions for "Cyclic/Circular Reference". You probably created 2 logical columns that are dependent on each other. As for column A, you are using the value from column B. And same for column B, you are using the output of column A. It's a deadlock.

The seriousness depends on your use of data from those columns as they will never give you output. If they are a must for your report, this is serious :) and you have to fix this.

You are not giving us a whole lot to go by. If I read your problem correctly, the initial refresh is the issue, subsequent ones work.

From my perspective, there are two possible issues here:

• The software version you are using is buggy, as others have suggested. See also this link, which suggests you could uninstall/reinstall the desktop client you are using. However, just like in the case that post author describes, it seems to present itself as a mere annoyance, nothing that seems worrisome, provided that the results you get are accurate otherwise.
• Alternatively, it could be a true circular reference that somehow gets resolved in between, but I doubt that. Here is another link describing circular references in detail.

If this were me, I'd try the uninstall/reinstall and see if that indeed fixes it. Otherwise, I'd probably ignore it.

Try refreshing the data for Table 1 first then refresh all the tables that should resolve the issue.