Live, Rapid Dev Guided by Kscope12 Attendees

All Things Oracle on 17 May 2012 with 0 comments

Attendees to this year’s ODTUG Kscope conference will have the opportunity to get involved in a live software development experience on the Red Gate exhibition stand (stand no. 424 – 425). Attendees will provide input to go from zero to first prototype in 3 days through a series of rapid development sessions live on the stand. Monday’s feedback is Tuesday’s… Continue Reading →

Free eBook: Expert Oracle Database Architecture

All Things Oracle on 23 April 2012 with 0 comments

Download your FREE eBook Expert Oracle Database Architecture (Apress Media) provides a one-stop resource containing deep wisdom on the design, development and administration of Oracle applications, written by one of the world’s foremost Oracle experts, Thomas Kyte. This fully revised second edition covers the developments up to Oracle Database 11g. Each feature is taught in a proof-by-example manner, not only… Continue Reading →

An Introduction to 11.2 RAC Server Pools

Aman Sharma on 18 April 2012 with 7 comments

Oracle RAC is designed to cater for Oracle specific applications and also non-oracle applications. These applications, both Oracle and non-Oracle, when deployed on RAC, are termed as resources and Oracle RAC can manage both kinds of resources on the clusterware stack. Examples of both oracle and non-oracle resources are: database instance, database services, xclock, Apache etc. The traditional way to… Continue Reading →

Dynamic Sampling (II) – Controlling the Activity – Part 2

Randolf Geist on 15 March 2012 with 1 comments

In the first part of this post I’ve provided a table that summarizes the Dynamic Sampling levels on session / system level. In the “Blocks Sampled” column there were numbers in brackets for the level 3 and 4 description. In the second part of this post I’ll explain why. DYNAMIC_SAMPLING_EST_CDN In the presence of statistics Dynamic Sampling behaves differently: For… Continue Reading →

The 40 Most Common Oracle Errors

David Njoku on 12 March 2012 with 12 comments

I have been in this industry long enough to remember the bad old days, when every developer and DBA had a pile of dusty Oracle user guides on their desks and, every time their database or application coughed up an error, would thumb through the books with mounting desperation. Fortunately, the times have moved on and we now all outsource… Continue Reading →

Dynamic Sampling (II) – Controlling the Activity – Part 1

Randolf Geist on 08 March 2012 with 2 comments

I’ve closed the introduction to Dynamic Sampling with an odd test case result: Although all table data was read by Dynamic Sampling the cardinality estimate of the optimizer was still way off – not quite what one might expect. The reason for this odd behaviour can be explained by the fact that Dynamic Sampling behaves differently depending on whether statistics… Continue Reading →

Virtualization

Jerry Ireland on 02 March 2012 with 3 comments

Overview Virtualization is a hot topic in the IT world. What is virtualization and why is it so popular? First of all, virtualization is not a new concept. It was introduced in the 60s to partition large mainframes in order to utilize their full power. These partitions allowed mainframes to “multitask”. Today’s systems can also benefit from virtualization, not so… Continue Reading →

Caching Part 2

Patrick Barel on 23 February 2012 with 5 comments

Never trust a computer you can’t throw out of a window. Steve Wozniak Deterministic Function Caching A function is considered deterministic if the outcome is the same if the input values are the same. Another thing is that the program should have no side effects. All the program changes are the return value and any out parameters. It is because… Continue Reading →

Caching Part 1

Patrick Barel on 14 February 2012 with 0 comments

To err is human, but to really foul things up takes a computer. – Farmers’ Almanac (1978) While programming in the Oracle Database you interact a lot with the data in the tables. Retrieving this data from the database involves context switching between the PL/SQL Engine and the SQL engine. This takes up a relatively large amount of time. You… Continue Reading →

Dynamic Sampling (I), an Introduction – Part 2

Randolf Geist on 08 February 2012 with 0 comments

If you follow me on my blog you might wonder if I let you get away without an actual test case, and of course I won’t do so. Here is a simple test case that demonstrates Dynamic Sampling in action: set echo on timing on time on drop table t; purge table t; — Create a sample table create table… Continue Reading →