SQL error when adding a view filter for a subqueue

If you define subqueues for a node queue (e.g. a smartqueue based on taxonomy), then try to add a filter to a view to restrict it to a specific subqueue, you get SQL errors. The fix is trivial: you were declaring the filter in the $tables array with a specific name (qid_N), so that the filters would be unique, but those unique names are not the field you actually need in the query. ;)