Wednesday April 15 at Collaborate 2015 Las Vegas room Mandalay K
For more information see Pythian’s Blog post.
What is Oaktable World ? Oaktable World is a day organized by members of the Oaktable network. The Oaktable network is a network of Oracle database tuning geeks. Among the members are Tanel Poder, Jonathan Lewis, Cary Millsap etc. Oaktable network was created by Mogens Nørgaard back in 2001 or so and Mogens started (more...)
In my previous article I started exploring the memory usage of a process on a recent linux kernel (2.6.39-400.243.1 (UEK2)), recent means “recent for the Enterprise Linux distributions” in this context, linux kernel developers would point out that the kernel itself is at version 3.19 (“stable version” at the time of writing of this blogpost).
The previous article showed that every process has its own address space, and that different (more...)
There are 5 parameters that are all prefixed with ‘sec’ in an 11g and 12c database. Actually that is a lie because one is now deprecated in 12c. They are all, as you might guess related to security. This blog is about changes in the default values and some thoughts about whether or not the default value is appropriate or not.
LPAR stands for Logical Partitioning and it's a feature of IBM's operating system AIX (Also available in Linux). By abstracting all the physical devices in a system, LPAR creates a virtualized computing environment.
In a server; the processor, memory, and storage are divided into multiple sets. Each set in a server consist of resources like processor, memory and storage. Each set is called as LPAR.
One server can have many LPARs operating (more...)
The NoSQL camp put performance, scalability, and reliability front and center but lost the opportunity to take the relational model to the next level because—just like the relational camp—it mistakenly believed that normalization dictates physical storage choices, that non-relational APIs are forbidden by the relational model, and that “relational” is synonymous with ACID (Atomicity, Consistency, Isolation, and Durability). The NoSQL camp created a number of innovations: functional segmentation, sharding, replication, eventual consistency, and schemaless design. (more...)
One of the big changes for Oracle Applications DBAs in EBS 12.2 is the introduction of online patching. Instead of using adpatch to apply application patches we now use adop. In order to allow for online patching Oracle has introduced the dual file system (Run and Patch). I'm not going to go into a complete explanation of the dual file system in this post, but you can think of it as being two copies (more...)
This came up in a (fairly typical) question on OTN recently where someone had the task of “deleting 6M rows from a table of 18M”. A common, and perfectly reasonable, suggestion for dealing with a delete on this scale is to consider creating a replacement table holding the data you do want rather than deleting the (more...)
I don’t travel as frequently as some people do, but with OpenWorld and various Oracle conferences each year, I definitely see my fair share of the inside of a plane and a hotel room. To pass the time on flights, I try to read, but when you’re reading on a work-based trip, it’s a case of reading a page or two here and there, rather than a true extended session of relaxed reading.
This blogpost is about finding the actual amount of memory a process is taking. In order to do so, this post dives into the memory mechanisms of Linux. The examples in this article are taken from an Oracle Linux version 6.6 server, with kernel 2.6.39-400.243.1 (UEK2). This is written with the Oracle database processes in mind, but actually uses examples of a processes running ‘cat’, which means the contents of (more...)
Guess what? OakTable World at IOUG C15 is happening. Last year, we’ve had awesome sessions and wonderful attendees. It was so successful that we have now a bigger room this year (there were other reasons too but hey — we can fit more people now!).
What: OakTable World C15 When: Wednesday, 15-Apr-2015, 8:00am – 5:30pm Where: Mandalay Ballroom K
I really hope if you are reading this, you would be in Vegas between 12th (more...)
Simple if there are no roles which are granted DBA role and allow me to show what can go wrong.
Create ROLE “secret”, Grant DBA to “secret”, Grant “secret” to USER “michael”
ARROW:(SYS@hawklas):PRIMARY> create role secret;
ARROW:(SYS@hawklas):PRIMARY> grant dba to secret;
ARROW:(SYS@hawklas):PRIMARY> grant secret to michael identified by michael;
When a simple SQL is used, “secret” is a ROLE NOT USER.
What is SQLcl ? SQLcl is a new command line interface like SQL*PLUS coming along with SQL Developper 4.1 Early Adopter. It is lightweight tool (only 11MB) developed by the SQL Developer team fully compatible with Windows and Unix/Linux. You don’t need to install it so it is totally portable. The tool does need any Oracle … Continue reading SQLcl, a revolution for SQL*Plus users→
In physics, one important limitation of any experiment is the fact that an act of observation inevitably interferes with the observed process (“observer effect”). Same thing is true about databases. It is a well known fact that, for example, turning on tracing can significantly slow down the process for which it’s enabled. But there exist even nastier forms of this effect: for example, when you try to trace a SQL statement using nested loop batching mechanism, (more...)