I found this thread quite interesting. As some who is hoping to learn more about internals, I would also love to see your “Life of a Query” presentation - particularly, to see to what level of detail you go to. =)
You also mentioned a Shallahamer-like paper. I would love to see something like that as well. I love when theory collides with reality and we mere humans get something we can sink our teeth into.
Thanks for your contributions,]]>
Agreed that you have an endless supply of detailed Exadata blog postings :) In fact, that was my initial source of information.
I was just wondering on that particular aspect: does it just pass the QEP nodes to the storage server?
…uh, I have how many blog posts on exadata ? :-)]]>
Thanks for checking out my blog.
To answer your question, for those I talked to, I’m pretty sure they got it. However, it does seem that the majority of people I talk to seem to think the database is chopping the SQL predicate text out of the query and sending it directly to the storage server.
Personally, I think it’s just a case of people not understanding query optimization and execution plans below the level of EXPLAIN PLAN. Many people don’t realize that the QEP contains actual nodes and that those nodes could be rewritten (as performed by the MSQ and KKFS subsystems) or shipped elsewhere (such as in parallel execution and certain RAC cases).
Of course, having never seen the source and having reviewed the Exadata architecture for no more than a day or so myself, I may be wrong. For all I know, Oracle may be generating some SQL-ish statement from the storage predicate nodes like it does for distributed queries, but I doubt it. Care to share more insight?
..is this still a source of confusion?]]>
Yes, the Life of a Query/Life of an Oracle Query presentation will be up soon. I have two versions of it, one that I did awhile ago and another which I did the night before the presentation. I prefer the newest one, but it’s a bit ugly and needs to be cleaned up a little.
Any plans to publish a link to your presentation? It sounds interesting.