I run a longtime running SQL query by clicking on GO button:

Await cmd.ExecuteNonQueryAsync(Me.cts.Token)

The command starts, lets say I have this query as part of corresponding command:

set nocount on;
declare @ID int=0
WHILE @ID<400000 BEGIN
    SET @ID+=1
    WAITFOR DELAY '00:00:01.000'
END 

Now when I click Cancel button (which call cts.Cancel()) it causes SqlException, whichs containts 2 errors:

1. “A severe error occurred on the current command. The results, if any, should be discarded.” (number 0)
2. “Operation cancelled by user.” (number 0)

I also different queries including INSERT statements. Everything worked fine, data was properly written.

So what is wrong?