GilaMonster (7/27/2011)
Errr, no...Non-unique clustered indexes get a uniquifier, which is 4 bytes (an int) added to rows that have duplicate values for the clustering key.
Nonclustered indexes get either the clustering key (complete with uniquifier) if the base table has a clustered index, or the 8-byte RID (file_id, page_id, slot_index) if the base table is a heap.
If the nonclustered index is unique, that's present only in the leaf level, if the nonclustered index is not unique that is present in the leaf and non-leaf levels.
Right. No more early-in-the-morning posts for me 🙂