jmeter – Variable Name must not be null in JDBC Request

January 6th, 2017
So Jmeter seems super cool. I've only used it a little bit but it does seem a bit touchy about somethings (like spaces in input fields) and the errors are often less than obvious and I'm not finding that much out there on google for the errors. Today I ran into the error Variable Name must not be null in JDBC Request   and Googling it didn't turn up anything. I'm pretty sure I ran into this same error a few weeks ago when I was first starting with Jmeter, so blogging here to document it. I was trying something new - running a procedure - instead ...


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jmeter – getting started

January 5th, 2017
This blog post is just a start at documenting some of my experiences with jmeter. As far as load testing tools go, jmeter looks the most promising to me. It has an active community, supports many different databases and looks quite flexible as far as architecting different work loads goes. The flexibility of jmeter also makes it hard to use. One can use jmeter for many other things besides databases so the initial set up is a bit oblique and there look to be many paths to similar results. As such, my understand and method for doing things will probably change ...


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Graphics for SQL Optimization

January 4th, 2017
Dan Tow, in his book SQL Tuning, lays out a simple method of tuning SQL queries. The method is Draw a diagram of each table in the query with Children above Parents Draw join lines between each join (many-to-many, one-to-many) Mark each table with a predicate filter and calculate the amount of table filtered out Then to find a great optimal optimization path candidate Start at the table with the strongest predicate filter (the filter that returns the fewest % of the table) join down to children (if multiple children join to child with strongest predicate filter) If you can't join to children, join up to parent The ...


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Apple Upset – upgrading to iPhone 7

December 22nd, 2016
Upgrading is always stressful - be it a computer, an Oracle database or an iPhone. There's always a good chance for lost data and lost time dealing with complications. So yesterday I picked up a new iPhone 7 from Verizon. The pickup was seamless. I had signed up for an upgrade program when I got the iPhone 6, so now I just walked in, gave them my old iPhone 6 and they gave me an new iPhone 7. It's bit scary giving up my old phone before restoring to my new phone, but I had a backup AND I asked Verizon to please ...


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Why does my full table scan take 10x longer today ?!

December 13th, 2016
Every so often a DSS query that usually takes 10 minutes ends up taking over an hour.  (or one that takes an hour never seems to finish) Why would this happen? When investigating the DSS query, perhaps with wait event tracing,  one finds that the query which is doing full table scans and should be doing large multi-block reads and waiting for “db file scattered read” is instead waiting for single block reads, ie “db file sequential read”.  What the heck is going on? Sequential reads during a  full table scan scattered read query is a classic sign of reading rollback and reading ...


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Amazon announces Performance Insights

December 2nd, 2016
Excited to see the announcement of Amazon RDS Performance Insight feature for database performance monitoring and tuning. Having met the team for this project I can say from my personal view point that the importance and future success of this feature is clear as day to me. The team is awesomely sharp, the architecture is super impressive, and this is by far the most exciting performance monitoring and feedback system I've been involved with,  surpassing the work I've been involved in on Oracle's performance monitoring and tuning system and Embarcadero's DB Optimizer and Quest Foglight and Spotlight. Not only does the feature ...


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SQL*PLus on Mac

December 1st, 2016
I would think installing SQL*Plus on the Mac would be point, click download, point click, install bam it works. Nah It did install mostly straight forward on my old Mac. Got a new Mac and no dice. Tried installing myself guessing at the downloads. First of all why isn't there just one download? Downloaded instantclient and instantclient with SQL*Plus which turns out to be correct, but no dice. Still got errors. Got errors. Gave up. Came back again to look at it yesterday and followed this: https://tomeuwork.wordpress.com/2014/05/12/how-to-install-oracle-sqlplus-and-oracle-client-in-mac-os/ worked like a charm. Then I ran a shell script that used SQL*Plus oramon.sh and get the error dyld: Library not loaded: /ade/dosulliv_sqlplus_mac/oracle/sqlplus/lib/libsqlplus.dylib Referenced from: ...


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Started at Amazon! … want to join me?

August 29th, 2016
(Disclamer: any opinions expressed here are fully my own and not representative of my employer) photo by alvaroprieto  (cc 2.0) Super excited to be working at Amazon on my passion which is performance data visualization and database monitoring. Suffice it to say this is the most excited I've been about work in my career and I've had ample opportunity to work on database performance in the past such as at Oracle (where I helped design the performance pages and designed Top Activity page), at Quest (now Dell) on Spotlight, on my own free tools ( ASHMon, S-ASH, W-ASH, Oramon etc)  and at Embarcadero ...


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Oaktable World 2016 Sept 19 & 20 is on !!

August 26th, 2016
Having take a new job at Amazon just two weeks ago and moving to Seattle (!)  I didn’t have the time nor was it practical to set up Oaktable World  this year. Luckily Kellyn Pot’vin has taken over the mantel ! Get the info straight from the horses mouth at her blog. The following content has been graciously supplied from Kellyn’s blog: Oak Table World is FREE to the PUBLIC!  We don’t require an Oracle Open World badge to attend, so bring a friend and they’ll owe you big time! Here is the current schedule: The Great Dane Mogens Norgaard will be opening Oak Table World on Monday, at 8:30am. Be ...


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Denial of Service (DoS) attacks continue

August 24th, 2016
It's frustrating to have to spend time jumping off into web security and wordpress configurations when there are so many other things that are important to be doing. Today the DoS continued and the Jetpack solution didn't seem to work. The other two solutions from Digital Ocean didn't seem reasonable. One was to re-install wordpress with there install version. Nice that they offer a better security protected version but I didn't feel like re-installing my wordpress. TH other option basically eliminated all access to xmlrpc.php. Looking around I found a plugin that does firewall work and had just added functionality for ...


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