Category: Databases

Databases are the systems of record at the centre of the enterprise. They exist to ensure correctness, durability, and control over critical data.

For decades, they have been optimised around human interaction – predictable query patterns, bounded concurrency, and clear operational ownership.

That assumption is now under pressure. As AI systems begin to interact directly with data, the database remains the point of truth… but the way it is accessed is starting to change.

Deprecation of Non-CDB Architecture in Oracle 12c

Back in July 2013, Oracle released the latest version of its flagship database product, Oracle 12c. Among the usual fanfare was information about a number of new options - including one known as Multitenant. With the Multitenant option, databases use a new architecture which features a container database (or CDB) which in turn contains one or more pluggable databases (or PDBs). … Continue reading Deprecation of Non-CDB Architecture in Oracle 12c →

Oracle AWR Reports: When IOStats Lie

If you've been unfortunate enough to follow my dithering on Twitter recently you'll know that I've been lurching between thinking that there is and isn't a problem with Oracle's tracking of I/O statistics in its AWR reports. I'm now convinced there is a problem, but I can't work out what causes it... so step 1 … Continue reading Oracle AWR Reports: When IOStats Lie →

Oracle AWR Reports: When Averages Lie

I was recently contacted by a customer who runs a busy ERP system on their Oracle database. Their users have been screaming for some time about unpredictable performance, where application screens which would usually open in under a second suddenly take an age. ERP systems are legendary for this, of course, because as each screen … Continue reading Oracle AWR Reports: When Averages Lie →

Postcard from Oracle OpenWorld 2014: The Oracle FS1 Flash Array

A couple of weeks ago I wrote a post about my trip to Oracle OpenWorld 2014 and the surprise announcement of the Oracle FS1 Flash Array. I posted it on the Violin Memory corporate website here: http://www.violin-memory.com/blog/postcard-oracle-openworld-2014-the-oracle-fs1-flash-array/ Follow the link to find out whether I thought it was the most amazing product in the history … Continue reading Postcard from Oracle OpenWorld 2014: The Oracle FS1 Flash Array →

Oracle, Parallelism and Direct Path Reads… on Flash

Guest Post This is another guest post from my buddy Nate Fuzi, who performs the same role as me for Violin but is based in the US instead of EMEA. Because he's an American, Nate believes that "football" is played using your hands and that the ball is actually egg-shaped. This is of course ridiculous, … Continue reading Oracle, Parallelism and Direct Path Reads… on Flash →

Viewing ASM trace files in VIM: Which Way Do You Use?

A couple of people have asked me recently about a classic problem that most DBAs know: how to view ASM trace files in the VIM editor when the filenames start with a + character. To my surprise, there are actually quite a few different ways of doing it. Since it's come up, I thought I'd … Continue reading Viewing ASM trace files in VIM: Which Way Do You Use? →

Oracle 12.1.0.2 ASM Filter Driver: Advanced Format Fail

[Please note that a more up-to-date post on this subject can be found here] In my previous post on the subject of the new ASM Filter Driver (AFD) feature introduced in Oracle's 12.1.0.2 patchset, I installed the AFD to see how it fulfilled its promise that it "filters out all non-Oracle I/Os which could cause accidental overwrites". … Continue reading Oracle 12.1.0.2 ASM Filter Driver: Advanced Format Fail →

Oracle 12.1.0.2 ASM Filter Driver: First Impressions

This is a very quick post, because I'm about to log off and take an extended summer holiday (or vacation as my crazy American friends call it... but then they call football  "soccer" too). Before I go, I wanted to document my initial findings with the new ASM Filter Driver feature introduced in this week's … Continue reading Oracle 12.1.0.2 ASM Filter Driver: First Impressions →

New AWR Report Format: Oracle 11.2.0.4 and 12c

This is a post about Oracle Automatic Workload Repository (AWR) Reports. If you are an Oracle professional you doubtless know what these are - and if you have to perform any sort of performance tuning as part of your day job it's likely you spend a lot of time immersed in them. Goodness knows I … Continue reading New AWR Report Format: Oracle 11.2.0.4 and 12c →