Posts Categorized: Pythian
I have been scanning some blogs by different teams involved with SQLserver 2005. There is a bit of cross linking happening so some articles are repeated on one or more blogs. Here is a short list:
It’s time for vacation for me.
I am off to Europe and then vising home – Sofia, Bulgaria. I will be back in 4 weeks. Yes I did earn to have a long vacation, and yes, Pythian is really nice in allowing me to have it all at once.
There’s always these little things that you discover when you read the manuals. For example the “duration” option for RMAN backup. It looks very neat, and is actually in RMAN from 10g Release 1.
James Foronda sent a link to his blog entry about silent data corruption in an Oracle-l discussion. He points out a new file system called ZFS that has self-healing features.I read all the slides and it really looks like something cool to try out. It has some features similar to Oracle’s ASM, such as dynamic adding of disks, self balancing etc. It’s fully transactional, supports snapshots, online everything. Auto striping (not sure how this would work). Very feature rich.
I was installing RAC, and during the clusterware install I picked up the wrong interfaces for public and private. What had happened was I had a 10.x.x.x IP on both eth0 and eth1, which was messing up the routing. The solution? Simply modify the VIP in the cluster configuration.
Finding duplicates with RANK – If you’ve made the mistake of forgetting a primary key on your table, it can be frustrating to find a way to delete all of the duplicate rows without deleting the initial instances. This query selects all of the ‘extra’ rowids and removes them.
Well I have been back from Collaborate 2006 for over a week now and decided that I should also make my presentation available from the Pythian web site. While there I participated in three sessions. I joined Michael Abbey, Ian Abramson, and Carl Dudley on a panel for the Non-Oracle DBA. My first presentation was PostgreSQL for the Oracle DBA. My second solo-presentation was Oracle 10g Data Pump 101.
If you have the ability to combine disk spindles at both the SAN level and Oracle (ASM) level, which one is better? Should you combine all your spindles on the SAN and present 1 big disk to OS and give that to ASM? Or should you present each individual disk spindle to ASM and let ASM do the mirroring? The disk group with 2 disks is slower! Those results are consistent, and confirmed with diagnostic output from iostat. You may start to wonder why would 2 be slower then 1. It should be twice as fast!
Did anyone else notice this interesting e-week article titled The Downside of Certification? It immediately reminded me of an article written by Pythian team lead and datawarehousing architect Rob Hamel titled “Get Down with OCP: Evaluating DBA Job Applicants in an OCP World”. What Rob noticed in 2004 was that certification can mask a certain type of incompetence from a casual technical evaluation process.
Tip of the hat to Eddie Awad who does some noticing and some digging to confirm that lnnvl(), a function that provides functionality similar to ANSI “Is Not True” and can be used to return boolean TRUE whenever the predicate to the function is either NULL or FALSE is now supported in 10GR2.