Step folding Unknown indicator error behind?

[xander2121]

Hello everyone,

In the Step foldin indicators there is an "Unknown" indicator which represents absence of query plan due to an error. How do I find out that error? 

[jjgb · Accepted solution]

Hi @xander2121, 

The step indicators are calculated by using the query plan. In "M", the query plan can be obtained by calling Value.Expression(Value.Optimize(...)) on the affected step.

For example, a known bug (under investigation) that will produce an "Unknown" step indicator is this:

let

  Source = Sql.Database("some_server", "some_database", [CreateNavigationProperties = false]),

  Navigation = Source{[Schema = "dbo", Item = "Tags"]}[Data],

  #"Removed top rows" = Table.Skip(Navigation, 4)

in

  #"Removed top rows"

I can obtain the error message by adding a new step that obtains the query plan for the affected step:

let

  Source = Sql.Database("some_server", "some_database", [CreateNavigationProperties = false]),

  Navigation = Source{[Schema = "dbo", Item = "Tags"]}[Data],

  #"Removed top rows" = Table.Skip(Navigation, 4),

  QueryPlan = Value.Expression(Value.Optimize(#"Removed top rows"))

in

  QueryPlan

Hope this helps. If you can, please share your query so we can track this as a bug.

Regards,

Jorge

[v-eqin-msft]

Hi @xander2121 ,

Could you please provide some details like when the error occurs and screenshots to help us clarify your scenario?

Best Regards,
Eyelyn Qin