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1
Q: 

On a Heap Table, what does a non-clustered index use as a pointer to a row?

Pick your version of SQL Server... if it has changed between version please specify if you know.

Build a table Add a non-clustered index on 1 or more columns. If I could dump a leaf block, what would I find as the pointer to the row in the table with the data?

+2  A: 

It uses a row id, which is basically a physical address of the row in the database: on Page X at Slot Y. If the row ever moves, then a Forwarding record is left in place so that the non-clustered index reference is kept valid. See Forwarding and forwarded records, and the back-pointer size.

Remus Rusanu  2010-08-10 23:02:17
that's was my assumption all along but MSDN didn't think anyone would want to know that so the section on Heaps is devoid of said information.
Stephanie Page  2010-08-10 23:16:21
"If the table is a heap, which means it does not have a clustered index, the row locator is a pointer to the row. The pointer is built from the file identifier (ID), page number, and number of the row on the page. The whole pointer is known as a Row ID (RID)." From http://msdn.microsoft.com/en-us/library/ms177484.aspx (Perhaps is not at the place you looked at)
Remus Rusanu  2010-08-10 23:19:55

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