Posted by Erland Sommarskog on 12/09/05 21:46

Mark D Powell (Mark.Powell@eds.com) writes:
> Looking at the query I noticed that the query does not have an
> available index and Query Analyzer shows that the full table scan is
> being done in parallel.
>
> My question: Does SQL Server change or modify its locking rules when
> queries are converted to be ran using parallel processing? If so, do
> you have a reference?

No. I would guess that what happens that both grab a table lock to
scan the table. When they found the row they are looking for, they
try to get an exclusive lock on that row, which they can't because the
other has a shared lock on the table.

> I have suggested adding an index to support the query.

That sounds like an excellent idea.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server 2005 at
http://www.microsoft.com/technet/prodtechnol/sql/2005/downloads/books.mspx
Books Online for SQL Server 2000 at
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