Batch Query Reduced from 12 hours to 45 Minutes

I was asked to look at a batch SQL query that ran for 12 hours on June 4th. I messed around with some other ideas and then went back to my best method for tuning long running batch queries. I ripped it apart. My code ran in 45 minutes.

This only works if you have the code and can change it. I work with a lot of PL/SQL code in Unix shell scripts running SQL*Plus. (more...)

Another On Call Week, Another SQL Profile (or two)

I was on call again last week and Sunday night I used a SQL Profile to fix a performance problem. We rolled out some updates Saturday night and the modified query ran fine in some cases, but others ran for hours. When I got on there were 60 sessions running the bad plan and the load on the system was very high. It took me a while to identify the good plan, but then I (more...)

Slides and My Impressions from May 17th AZORA Meetup

We have the slides from the two talks at our May 17th AZORA Meetup.

Here are Stephen Andert’s slides: Networking is NOT just cables and fiber!

Here are Doug Hood’s slides in three parts:

  1. Using SQL and PLSQL for Mid-Tier Database Caching
  2. Oracle TimesTen Scaleout – World’s Fastest OLTP DB
  3. Oracle In-Memory Data Processing

I wanted to share my impressions of the two talks and the meeting as well as share the slides. Of course, (more...)

MySQL Source Installs for each RDS version

I have been doing a lot of Oracle and PeopleSoft work this year, but I am trying to continue to develop my MySQL and Amazon Web Services (AWS) knowledge at the same time. My goal is to learn some new thing about MySQL and AWS each month and then document it either on this blog or on my company’s internal web site.

This month I decided to focus on building a Linux virtual machine on (more...)

Tried Live SQL

Quick post. I tried https://livesql.oracle.com/ for the first time.

Looks like you can try out the latest version of Oracle for free. You can type in SQL statements in your web browser.

There seem to be a boatload of scripts and tutorials to try out. Might be good for someone who is new to SQL.

Bobby

Installed 19.3 on Linux on VirtualBox

I noticed that Oracle database 19.3 was available to download so I installed it on a Linux VM under VirtualBox.

I cloned my base Oracle Linux 7 VM and did a yum -y update to get it up to the latest Linux version.

I installed the preinstall RPM:

yum install oracle-database-preinstall-19c

Created the Oracle home, set some variables, and disabled the firewall.

mkdir -p /home/oracle/product/db/19.0.0
chgrp oinstall /home/oracle/product/db/19.0.0
cd /home/oracle/product/db/19. (more...)

May 17th AZORA Meetup – Last until September!

Example of coe_xfr_sql_profile force_match TRUE

Monday, I used the coe_xfr_sql_profile.sql script from Oracle Support’s SQLT scripts to resolve a performance issue. I had to set the parameter force_match to TRUE so that the SQL Profile I created would apply to all SQL statements with the same FORCE_MATCHING_SIGNATURE value.

I just finished going off the on-call rotation at 8 am Monday and around 4 pm on Monday a coworker came up to me with a performance problem. A PeopleSoft Financials (more...)

Check your hints carefully

Back in 2017 I wrote about how I had to disable the result cache after upgrading a database to 11.2.0.4. This week I found one of our top queries and it looked like removing the result cache hints made it run 10 times faster. But this did not make sense because I disabled the result cache. Then I examined the hints closer. They looked like this:

/*+ RESULT CACHE */

There should (more...)

Huge Pages Speeds Startup of Web Servers

We had issues deploying changes to a large web farm a few weeks back. We had automated the startup of the 25 web servers using a DevOps tool but when it tried to bring them all up at once it took forever and the web servers got timeout errors. We resolved this by putting in huge pages on the metadata database.

I mentioned the unexpectedly large impact of huge pages on login time in a (more...)