Tom.Thomson (3/20/2009)

This is slightly wrong - it makes no difference whether the index is clustered or not. What's required for the query to run instead of waiting for the lock to be released is that the where clause of the query is such that the index (clustered or not) is used and causes the uncommitted row not to be visited so that the lock is not encountered.

At least this is true of SQLS 2000. I very much doubt if it's changed in later versions, since it delivers what MS wanted (high concurrency) for this isolation level.