Re: Raw vs. Cooked

From: Mark D Powell <Mark.Powell_at_eds.com>
Date: 18 Dec 2004 20:42:20 -0800
Message-ID: <1103431340.340533.24860@z14g2000cwz.googlegroups.com>

db_file_sequential_read is a count of random (single block) IO requests. Most indexed access falls into this category: get a branch block, get a leaf block, get the table block. When used in conjuction with the other IO statistics it helps you determine the distribution of your Oracle IO by type: full table scan verse indexed, number of IO expended on sort operations, etc....

When the statistic is used at the session level it can help you determine if a plan is efficient. That is you can estimate the number of IO operations a task should take and then compare the statistics to the estimate.

HTH -- Mark D Powell -- Received on Sat Dec 18 2004 - 22:42:20 CST