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Hello,
Having downloaded the latest version of Power BI desktop (Version: 2.104.702.0 64-bit (April 2022)), we are now encountering an "A cyclic reference was encountered during evaluation" exception when refreshing the data from a MySQL database:
We've traced the issue to the use of a Parameter named `Schema` in the Power Query as follows:
let Source = MySQL.Database(Server, Database, [ReturnSingleDatabase=true]), <query name> = Source{[Schema=Schema,Item="<table name>"]}[Data] in <query name>
A refresh of the data preview in the Power Query Editor works without any issues, it is only when we attempt to reload the data in the Power BI report that the exception is generated.
The issue is with the following specific snippet in the query:
Schema=Schema
The solution / workaround is to rename the Parameter to something other than "Schema". For example, the reload works as it did before if we change the query to use a new Parameter called "SourceSchema":
let Source = MySQL.Database(Server, Database, [ReturnSingleDatabase=true]), <query name> = Source{[Schema=SourceSchema,Item="<table name>"]}[Data] in <query name>
Whilst the use of a Parameter name which collides with a Power Query attribute name isn't a good principal to adopt, the concern is that this code has been working for months and is only generating an exception with the new version of Power BI Desktop.
The concern is that other users may have adopted this convention in their own Power BI reports and will therefore encoutner the same issue where:
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