Andy

Hi Andy, well Im not sure about this article and its validity in some areas.

My only real concern in the title of the article, I believe that is not "bad practice" NOT to use clustered indexes, in 6.5 days this may be the case re hot spots etc, but v7 onwards its not an issues. Worst still, I firmly believe its GOOD practice not to use clustered indexes, especially on identity column keys (which seem to be popular with sqlserver programmers rather than natural keys). As you can only create one clustered index over a table one should carefully plan the creation of the key to maximise performance. I beleive their is little performance gain on placing a clustered index over an identity column when a natural or other combo key will yield better performance and query optimiser hit rates. This is especially the case when the default pkey index is type clustered, which is bad practice on Microsoft's part!

What is bad practice, as you mentioned, is no p-keys.

Perhaps worth mentioning that f-keys should also be indexed. This is a common performance gain in oracle and holds true in most dbms's. Funny enough, many people forgot them and end up indexing later on some strange concatenation of columns that the optimizer cant used in joins.

Cheers

Chris