Author Archives: Bobby

I got the following Facebook message about the East Coast Oracle Users Conference which starts in less than two weeks: It’s Friday and ECO is just 12 days away. Looking forward to seeing everyone! Please spread this discount code to … Continue reading →

I was getting some bad spam users registering on this blog so I disabled the ability to register.  You don’t really get any benefit from registering so I’m saving people time and blocking spam.  Anyone can leave a comment without … Continue reading →

I had a situation where I wanted to compare the temp space used by two similar insert statements on a test system.  One was filling up the temporary tablespace and the other wasn’t. select sql_id,sample_time, sum(TEMP_SPACE_ALLOCATED)/(1024*1024*1024) gig from DBA_HIST_ACTIVE_SESS_HISTORY where … Continue reading →

Quick post of a query I just used to diagnose a problem with a SQL statement that had a lot of db file sequential read waits.  This uses ASH data to see which segment the waits were on the most. … Continue reading →

I spent the past four days in SQL Server 2012 performance tuning class with four of my coworkers.  It was so surreal walking into the Microsoft offices on the first day.  I kind of felt guilty after all these years … Continue reading →

Prepping for my Intro to SQL tuning talk on Monday I did a little further research on one of my examples.  It is a concept I’ve known about for a while and I feel like it is profound evidence for … Continue reading →

Spent several hours practicing my Introduction to SQL Tuning talk yesterday and it has made me think through the things I’m saying.  I don’t want to lead anyone astray by my talk, or the things I’ve posted on this blog.  … Continue reading →

Earlier today I was getting paranoid and thought I had found an error in my “Intro to SQL tuning” paper namely that there were more than n! join orders. Here is what I said in the paper: There are many … Continue reading →

This is a follow up to my previous post “Faster commit time with fewer sessions“.  I’ve put together a test case against an HP-UX server running 10.2.0.3 of Oracle that shows commits six times faster with shared servers than with … Continue reading →

I’m trying to understand how to prevent the database server that supports one of our web sites from becoming overwhelmed when the CPU %used gets too high.  Once CPU gets above about 80% performance takes a nose dive and CPU … Continue reading →