• Craig Farrell (11/19/2010)


    Hey Gus,

    Late to the party, I know, but you referenced this in another thread and I had a curiousity. Could you discuss the 'lazy updater' component a bit more. I'm not necessarily sure I understand how the 'temp range' vs. the 'real range' helps with update issues, since you're still locking and unlocking rows/pages/table using either column.

    The idea is to use Snapshot Isolation. That will allow the asynchronous update to complete without wrecking performance while it runs (which was a flaw in my original implementation). This could also be used in a purely nested sets hierarchy, so that infrequent updates don't interfere with concurrent reads. That's what I was refering to in that other thread.

    - Gus "GSquared", RSVP, OODA, MAP, NMVP, FAQ, SAT, SQL, DNA, RNA, UOI, IOU, AM, PM, AD, BC, BCE, USA, UN, CF, ROFL, LOL, ETC
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