I attended an excellent free seminar hosted by Oracle Ireland in September, where Tom Kyte spoke about the topics below. He also did a Q & A session.
- Big Data
- All About Statistics
- Efficient Data Management
- Ask Tom Live – Question and Answer session
It’s been many years for me since I worked in pure technical roles, and I was expecting to be quite lost in the statistics & Data management sessions, but I’m glad to say Tom explained it in a way I could understand. In fact I was surprised how much I remembered from those days,
Big Data is a term I had heard a little about, but it’s not frequently used in Oracle Ebusiness clients, so it was very useful to get the overview from Tom on this subject. I will talk about Big Data in a later post so stay tuned for this.
All about Statistics:
Tom’s discussed why we gather statistics, how to gather them, how they can be mis-used, and went through some very detailed examples of how statistics can result in the wrong query plan. He also went through some examples of how developer make life difficult for DBA’s by using the wrong data type, using ‘fake’ values, or by abusing functions.
Tom’s key Takeaway: As a DBA you must understand the data to be able to accurately diagnose a problem. Without understanding the contents & spread of data in problem areas, it is impossible to resolve any issues.
Efficient Data Management:
Tom talked about Partitioning & Indexing, Managing Statistics, Compression, Purging & Backup activities. The most interesting part of this for me was in relation to backup, “the fastest way to do something is not to do it”, where Tom talked about options to avoid backing up, while achieving the same result. He offered a couple of options:
- Make tablespaces read-only & backup once
- Dont do indexes
- Use Compression wherever available
Tom’s key Takeaways: “The fastest way to do something is not to do it.”, “Statistics is not a game of perfect, decisions on representative data is good enough”
Ask Tom Live – Question and Answer session:
This was the best part of the day, where the audience asked their questions, and really got value from Tom’s extensive experience.
In the Q&A session he was able to show his sense of humour, and he provided a few memorable quotes:
“The junior DBA who has just read a tuning book is not the guy to let loose on your production database.”
“Plans you make for large-scale data, will also work for small.” Why not plan using large data sets in the first place?
“DBA’s should like & recommend solutions that involve Restore, as it provides a chance to practise”. Take every opportunity to backup and restore, to develop and confirm your backup strategy.
Overall this was a thoroughly enjoyable session with one of the Oracle experts of our time. I would highly recommend taking any opportunity to go and hear Tom speak.
For those who want to review the materials in more detail, the link is : Dublin_Sep_2012.zip
The Ask Tom site is also a resource I recommend – any technical issue you will encounter is probably already answered on this site, and if by some chance it’s not, you can ask him to solve it!