Archives of the TeradataForum

Message Posted: Wed, 16 Mar 2005 @ 13:32:30 GMT


	<Prev	Next>		<<First	<Prev	Next>	Last>>

Subj:		Re: TPump Update

From:		Victor Sokovin

Keith,

I may have phrased it badly, but the point I was trying to make is that row locking is actually "row hash" locking, as the manual says...

A row hash lock applies to a set of rows that shares the same hash code. It does not necessarily, nor even generally, lock only one row.

Thanks for the feedback. I think I understood that part. In Bill's case, if I understand it correctly, there is a one-column UPI and exactly that column is used in the WHERE clause of the UPDATE. I think this makes the statement fully qualified in the sense that TD should apply row-hash locks rather than table level ones. Even if it packs 50 statements in one MSR, I still makes it 50 rows (it is a UPI). What I could not understand from your original remark was that you said that there might be more rows locked than the PI suggests. Can it really be happening in this example?

Regards,

Victor