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Secret hacking session – full scans, direct path reads, object level checkpoints, ORA-8103s!

At the last week’s Expert Oracle Exadata virtual conference both me and Kerry touched the topic of how smart scan (and direct path read) decisions are done for each scanned segment during the SQL execution runtime – and not by the optimizer during the optimization phase.
I got a few follow-up questions about this yesterday and I also recall a similar question after my Understanding Exadata Performance Metrics presentation I did for UKOUG in London in April.
I think this is a topic which deserves some deeper coverage and so I decided I’ll do another secret hacking session on Tuesday 9th August (2011) 9-11am PDT.
The topics (hopefully) covered will be:
  1. How do full table scans work
  2. How and why do the “ORA-8103: object no longer exists” happen
  3. How does Oracle (11g) decide between a buffered full table scan and a direct path read scan (plus smart scan in Exadata)
  4. What’s the difference between an object_id and data_object_id?
  5. and more!
Note that while I do touch the Exadata topic a bit too, this session is generic and useful for anyone full scanning tables on any Oracle database… :)
This event is free and you can sign up here:

P.S. I will record the event and publish the video too. So if you’re in Australia or Hong Kong, no need to stay up late ;-)