Reply from gunjandavid on Aug 14 at 1:16 AM may be normalization will help better...
| | | ---------------Original Message--------------- From: Tom Falconer Sent: Monday, August 13, 2012 1:38 PM Subject: I/O Spike but no Change in Explain Plan Is it as simple as the data was in the SGA on one day, and not on the other? The extra IO could easily be the result of another query, only run occasionally, filling the SGA with its own data, so this run needs to re-read it all from the database, whereas it normally sits in memory. Unless this caused a problem, it probably isn't worth worrying over. If it did cause a problem then you need to spend some time working on the performance of the query assuming that the data is NOT in the SGA. This is just a guess based on the information you have given, and there could be other reasons the data needed to be re-read. Regards, Tom | | Reply to this email to post your response. __.____._ | _.____.__ |
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