这两种索引都可以指定索引操作符类并按照降序或升序排列。

Both can specify an index operator class and both can be sorted in ascending or descending order.

youdao

存在于表上的索引，包括它们索引的列，哪些是升序或降序的，以及哪些是群集的。

The indexes that exist on a table, including the columns that they index, whether they are ascending or descending, and whether they are clustered.

youdao

如果你深入一个索引的各项，会看到他们是有序的，通常升序，但从8i开始，也可以降序。

If you could walk through the entries in an index, you would see that they are in order, usually ascending, but since 8i, descending also works.

youdao