RE: does oracle use block level locking with RAC?

From: Ric Van Dyke <>
Date: Fri, 9 May 2008 13:51:49 -0500
Message-ID: <>

There are locks and then there are locks.  

Your right Oracle locks ROWs not blocks. However, when in RAC only one instance "owns" the block at a given time. I forget all the techno garble to describe the mechanism right now but when another instance wants to change a block it requests to be the owner of that block if it isn't at the time the change is being made. So it sure seems like a lock because you can't access the block until you own it. But it's not a lock in the sense that most of us think of a lock. Is that confusing enough? :-)  

Ric Van Dyke

Hotsos Enterprises

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[] On Behalf Of Rick Ricky Sent: Friday, May 09, 2008 2:39 PM
Subject: does oracle use block level locking with RAC?  

I saw on a board somewhere that someone is having deadlock issues due to block level locking with Oracle RAC? I thought Oracle always did row level locking on everything? Could this be a mis-perception with something else?

Received on Fri May 09 2008 - 13:51:49 CDT

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