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Oracle Exadata Storage Server: No More SQL Tuning Required? Hooray!

I sometimes wonder if folks think I prefer poorly-tuned SQL. After all, I like hardware and everyone knows how effective it is to throw hardware at a poor query plan. I think everyone in the world has already blogged it but I can’t resist the me-too excitement. On June 10 my fellow Oak Table Network [...]

Do-It-Yourself Exadata-Level Performance? Really?

Oracle Mix is hosting “Suggest-a-Session” for OOW 2010. I thought that sounded like fun so I did the following…see what you think: Do-It-Yourself Exadata-level Performance? Since my blog has been essentially dormant for 2 months I expect about 43 click-throughs and no more than 42 votes And, yes, I will kick up my blogging again [...]

Log File Sync and AWR – Not Good Bedfellows

I’m sure many of you are already enlightened enough about the dangers of ratios and averages, the most famous blunder of all being the ‘cache hit ratio’. It’s not that all ratios and averages are useless, but it is surely the case that most are useless, and that all can be misleading. This posting is [...]

DBMS_PARALLEL_EXECUTE

Here is a recent thread from OTN forums. The question raised is WTF? whether a hint in the examples section of DBMS_PARALLEL_EXECUTE documentation have to be used or not and why it is there. What do you think about it? Have a look in the documentation and mark your choice in a poll: PS. In [...]

Aanmelden AMIS Query: “An Evening with Doug Burns”

Doug BurnsOp donderdag 17 juni, vanaf 18:00 uur, zal Oracle Database Expert en Oracle ACE Director Doug Burns(Schotland), een kennisavond vullen met live demo’s op basis van de Oracle Enterprise Manager Diagnostic en Tuning Pack.

Deze bijzondere avond, geheel zonder slides, met de naam “How I Learned to Love Pictures – Oracle 10g/11g Performance Analysis Using OEM” zal alle in en outs van de Oracle Enterprise Manager Diagnostic en Tuning pack in geur en kleur, de valkuilen en de verstopte juweeltjes van de Oracle Enterprise Manager, demonstreren gebruik makend van onder andere Swingbench. Voor meer informatie, over Doug Burns of de inhoud van deze presentatie, zie de volgende blog posts en URL’s:

Wil je er bij zijn dan kun je je aanmelden voor deze AMIS Query, via de volgende URL:

8-)

Enabling and Disabling Database Options

One of those small items that is easy overlooked (at least I overlooked it...) and I think, arrived with Oracle database version 11.2, at least on Windows/Linux...

The Oracle 11gR2 Database Installation Guide for Windows described a new tool, at least for me, that enables or disables database features on Windows. In the manual it is described as follows...

When you install Oracle Database, certain options are enabled and others are disabled. If you must enable or disable a particular database feature for an Oracle home, then shut down the database and use the chopt tool. See Example 5-1.

The chopt tool is a command-line utility that is located in the ORACLE_HOME\bin directory. The syntax for chopt is as follows:

chopt [ enable | disable] db_option

The possible values for db_option described in the following table.

“Flash” Storage Will Be Cheap – The End of the World is Nigh

A couple of weeks ago I tweeted a projection that the $/GB for flash drives will meet the $/GB for hard drives within 3-4 years. It was more of a feeling based upon current pricing with Moore’s Law applied than a well researched statement, but it felt about right. I’ve since been thinking some more [...]

Oracle memory troubleshooting article

Randolf Geist has written a good article about systematic troubleshooting of a PL/SQL memory allocation & CPU utilization problem – and he has used some of my tools too!

http://oracle-randolf.blogspot.com/2010/05/advanced-oracle-troubleshooting-session.html

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Extended statistics and function-based indexes

About a year ago I’ve discovered nice feature of Oracle 10gR2 CBO: to overcome an issue with calculated selectivity for predicates on multiple columns, it can use DISTINCT_KEYS of the available index. Couple of weeks ago the bug fix mentioned in the OTN thread actually helped to solve a performance issue of a query. And [...]

Oracle Exadata Delivery Day

Well our new Exadata showed up this week. We had a pretty nice lab environment already. A bunch of Dell’s, some IBM’s, several Sun’s. We have a couple of EMC Sans as well (we actually threw away a whole EMC rack to make room for the Exadata). And of course we have every version of Oracle from 8i to 11gR2. It’s a good learning environment. It also let’s us try things when clients have a specific set of versions that we want to mimic. So now we have an Exadata V2 as well. We’ve had the delivery date on the calendar for several weeks. For some reason it reminded of the Weird Al Yankovik song Weasel Stomping Day.