Re: Snapshot Logs/Triggers

Yep, know the background nuts and bolts just fine ... and that's what the core of the question is. The inserts into the snapshot logs and/or related trigger firing increases commit response time. Small groupings of transactions are not visibly effected, but as you scale, the extra overhead comes at a very measurable and obvious cost. Moreover, lets say your prod instance morphs such that your reporting instance needs to reflect that, you're then potentially managing more snapshot logs and/or triggers. I'm curious as to whether others have encountered this and what normal, perhaps DW tending options, are out there ...

:-)

NetComrade wrote:
>
> snapshots work out good for us..
> snapshots, btw, involve triggers created on the background to update
> snapshot log.. snapshot log keeps track of inserted/updated/deleted
> rows..
> I refresh snapshots every hour.. results in a couple of thousands of
> rows.. takes few min.. not a big hit on production system.
>
> On Tue, 27 Nov 2001 22:20:01 +1100, Casey Dyke <cdyke_at_froggy.com.au>
> wrote:
>
> >Folks,
> >
> >Am curious to know what setup others may have employed when trying to
> >shift incremental data (ie: only that that has changed) from one
> >instance to the next (prod --> reporting). Snapshot logs or triggers
> >quite easily facilitate this, but come at a cost. Has anyone avoided
> >them due to said cost and, if so, how'd you dig out?
> >
> >:-)
>
> .......
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Received on Tue Nov 27 2001 - 15:16:39 CST