----- Original Message ----- From: "Tanel Poder" <tanel@xxxxxxxxxxxxxx>
To: <karlarao@xxxxxxxxx> Cc: <kylelf@xxxxxxxxx>; "ORACLE-L" <Oracle-L@xxxxxxxxxxxxx> Sent: Saturday, May 21, 2011 3:25 PM Subject: Re: SQL ordered by Physical Reads (UnOptimized)
These slides fail to mention that the optimized reads statistic is also incremented when smart scans can "optimize IO" by avoiding doing it thanks to storage indexes. So, if your OLTP database has some smart scanning happening in it (usually thanks to various reports, etc) then the optimized reads may be either due to flash cache hits or storage index IO elimination. -- Tanel Poder http://blog.tanelpoder.com
And why is my laptop reporting optimized reads ? Regards Jonathan Lewis http://jonathanlewis.wordpress.com -- //www.freelists.org/webpage/oracle-l
