Merge branch 'column-ordering' into aehrc-master

input/pagecontent/StructureDefinition-ViewDefinition-notes.md

@@ -353,7 +353,8 @@ And, the equivalent with nested structure:
 Note the former example is preferred due to its simplicity and the latter is included purely for illustrative purposes.
 
 ### Column Ordering
-*View runners* MUST produce output in the order that the columns appear in the ViewDefinition.
+
+*View runners* that support column ordering in their output format MUST order the columns of the result to match the order that they appear in the ViewDefinition.
 
 `select`s that have nested `select`s will place the columns of the parent `select` before the columns of the nested `select`, and the columns from a `unionAll` list are placed last. To change the column ordering, it is possible to place the columns or the `unionAll` in a nested `select`, which can be ordered relative to other nested `select`s as desired.