Strange error when appending

[AlB]

Hi all,

we have two tables:

- T1, imported from Snowflake

- T2, imported from PBI dataflow A2. Dataflow A2 pulls in turn from another dataflow, B2

I can read T1 and T2 into Power Query, do some changes on them and load them on the model, separately, without problem.

I then do a simple append of both tables on a separate table: 

let
    Source = Table.Combine( {T1, T2})   
in
    Source

The preview for the append in PQ works well, no complaints, but when I try to load the new table into the model, I get the error message below.  Any idea what the issue might be?

Many thanks

[AlB]

Thanks @v-xiaotang 

The first link is not working

[v-xiaotang]

Hi @AlB 

Actually, M engine error is usually related to the data source. Please check the advanced editor.

I also find 2 related links, will they help?

Failed to save modifications to the server. Error returned: 'M Engine error: ''. '.

AAS Processing Error “Error returned: 'M Engine error: 'Microsoft.Data.Mashup; Token Comma expected”...

Best Regards,

Community Support Team _Tang

If this post helps, please consider Accept it as the solution to help the other members find it more quickly.

[jennratten]

Hello - In the dataflows, is the option checked to allow combining data?  Do the names of the tables being appended have any special characters (not sure if T1 and T2 are the real names)?

[AlB]

Thanks @jennratten 

That option was not checked. It is now but I'm still getting hte same error.

Names of the tables no special characters. Actual names are

t1_

t2_

[jennratten]

Have you refreshed the dataflows?

[AlB]

@jennratten 

I have. Still the same error.