Select transform (Schema-based) result order is not predictable #20047
Description
pipeline.apply(Select.fieldNames("x", "y"))
pipeline.apply(Select.fieldNames("a", "b"))
The returned output order is not predictable. In the above two examples, field x may return first, while field a (also queries in the first place) may return in the second place.
Shall we add withOrderByFieldInsertionOrder to fieldAccessDescriptor in Select PTransform, so that the return order is predictable?
Imported from Jira BEAM-9016. Original Jira may contain additional context.
Reported by: yangzhang.