- * We provide two different interfaces to what is essentially the same
- * code: one for sorting HeapTuples and one for sorting IndexTuples.
- * They differ primarily in the way that the sort key information is
- * supplied. Also, the HeapTuple case actually stores MinimalTuples,
- * which means it doesn't preserve the "system columns" (tuple identity and
- * transaction visibility info). The IndexTuple case does preserve all
- * the header fields of an index entry. In the HeapTuple case we can
- * save some cycles by passing and returning the tuples in TupleTableSlots,
- * rather than forming actual HeapTuples (which'd have to be converted to
- * MinimalTuples).
+ * We provide multiple interfaces to what is essentially the same code,
+ * since different callers have different data to be sorted and want to
+ * specify the sort key information differently. There are two APIs for
+ * sorting HeapTuples and two more for sorting IndexTuples. Yet another
+ * API supports sorting bare Datums.