Posts Categorized: Technical Blog
I was reading my session evaluation results and came accross comment that said: “copy and paste coder.” I’ve been doing this specific presentation for almost 5 years now with a few tweaks every once in a while based on feedback. Yes, I live and breathe disaster recovery as part of my day-to-day job. However, there are several reasons why I do not type nor write code during my presentations. Here are a few of them.
In this follow up post: I’m going to provide notes and diagrams as well as answer questions from my web cast on Oracle 11G SCAN – RAC SIG. Let’s get into it….
While trying to move a schema from one MySQL server to another, I encountered a very odd issue. The schema to be moved contained both MyISAM and InnoDB tables, so the only option I had was to dump the schema using mysqldump on the source server and import it on the destination server. I did some digging and found that the problem was that the MyISAM engine silently changed the table definition without any indications. Here are some solutions.
No, this isn’t a re-post of my earlier blog about bug 1233183.1. We’ve found a fun new bug that seems to be specific to our poor standalone ASM instances when upgrading from Oracle Grid Infrastructure 126.96.36.199 to 188.8.131.52.
We have a client that runs an application that, for whatever reasons, does NOT like daylight saving time. For that reason, the Oracle server is kept in Eastern Standard Time and does not change with the rest of the eastern United States when DST begins and ends every year. They accomplish this with a custom /etc/localtime file. However, they left /etc/sysconfig/clock set to “TZ=America/New_York,” which would prove fateful as I shall point out.
Summer’s here, and that means it’s time to start thinking about Oracle OpenWorld 2011. Pythian’s plans are well underway. We have been busily planning since March, have submitted a number of abstracts on all sorts of topics: Exadata, ASM, GoldenGate, ADR, ASM, many based on real world experiences with Pythian clients. Some have been accepted, but we’re hoping for a few more and we’re asking Pythian fans to vote for our sessions on Oracle Mix.
I was working on a task where I had to confirm if the direct IO is in use or not. filesystem_io_option database parameter was set to “DIRECTIO” to make use of directio. Initially I was looking for same kind of memory structures in Solaris but could not find so ( bad luck :( ) and so used basic tracing using truss.First I logged into database and check the filesystem parameter ( Changed the name of the database and host :) )
In this blog, i’m going to review a recent MySQL upgrade I have done on one of the systems I am involved in administering. This is a real world example of an upgrade project, and hopefully when we’re done, there may even be an overall performance boost.
Please join Pythian for our next series of live and recorded webinars and have the chance to ask questions directly of our DBA experts. If you miss a session, you can always check out select recorded webinars here
Using algorithm described in “Relational Database Index Design and the Optimizers by Tapio Lahdenmaki and Mike Leach”, I quickly came up with two indexes and while first one looked fine, I was really confused by the second one for the elimination of the sort. Let me show an example, not copy one from the book, but rather show a test I did with MySQL.