Forum Discussion
KimStahl94
4 years agoHelper I
Formula.Firewall Error which disappears after reloading the data model in PBI Desktop
Hi there, I was wondering if anyone could help me after I did not find any solution that helped me removing the following error: Formula.Firewall: Query 'Query1' (step 'Source') references other qu...
KimStahl94
4 years agoHelper I
Hi lbendlin ,
are there other transformations that I should avoid too? Like Invoking custom functions? It seems as if the error also appears for queries that do not have any merging steps at all. Therefore I use the expand function in the PQ UI that generates and invokes a automatically generated function.
Regards
KS
lbendlin
4 years agoSuper User
Avoid anything that makes the Power Query engine think it is dealing with separate data sources. If you browse the interwebs you will find all kinds of trickery to create a smoke curtain so that the engine gets confused, and assumes everything is ok.
Small example: declare functions inside your query, not outside.