This is going to be a very short post for a change. I have used Swingbench extensively and really love the tool. Many thanks to Dominic Giles!
Recently he announced a new tool on his blog that you can use to inflate your data volume. So instead of using the “-scale” argument when executing oewizard you can just keep the defaults and later on create as much data as you like. Here is an example, (more...)
Teaching is on the things I like doing, and currently I am investigating the Oracle 12c features around caching data in the various memory areas. Since the In-Memory (cost) option has been discussed by other far more knowledgeable people I would like to share some findings about the big table caching here.
In Oracle 12c you have two additional options to cache information: full database caching and big table caching. The first is (more...)
This post is the result of some testing I performed on Exadata data file creation. You may know that Exadata offloading incorporates SQL optimisations as well as some infrastructure work. For quite some time Exadata allowed the DBA to create data files a lot quicker than on traditional systems. This has been documented before, for example by @mpnsh here
The final comment on his blog entry was a remark that data file creation is quite (more...)
In the very lengthy previous post about the MAA connect string I wanted to explain the use of the MAA connection string as promoted by Oracle. I deliberately kept the first part simple: both primary and standby cluster were up, and although the database was operating in the primary role on what I called standby cluster (again it’s probably not a good idea to include the intended role in the infrastructure names) there was no (more...)
Sorry for the long title!
I had a question during my session about “advanced RAC programming features” during the last Paris Oracle Meetup about the MAA connection string. I showed an example taken from the Appication Continuity White Paper (http://www.oracle.com/technetwork/database/options/clustering/application-continuity-wp-12c-1966213.pdf). Someone from the audience asked me if I had experienced any problems with it, such as very slow connection timeouts. I haven’t, but wanted to double-check anyway. This is a (more...)
I recently applied system patch 20132450 to my 18.104.22.168.0 installation on a 2 node RAC system on Oracle Linux 7.1. While ensuring that OPatch is the latest version available I came across an interesting command line option in opatchauto. It is called “-generateSteps”.
[oracle@rac12sby1 ~]$ $ORACLE_HOME/OPatch/opatchauto apply -help
OPatch Automation Tool
Copyright (c) 2015, Oracle Corporation. All rights reserved.
Apply a System Patch to Oracle Home. User specified the (more...)
This is another post to remind myself that Oracle evolves, and what I thought I knew might no longer be relevant. So double-checking instead of assuming should become a habit!
Today’s example: direct path inserts. I seemed to remember from Oracle 9i that a direct path insert ignores referential integrity. This is still confirmed in the 9i Release 2 Concepts Guide, chapter 19 “Direct Path Insert”. Quoting from there:
During direct-path INSERT operations, Oracle appends (more...)
Do you know the difference between exp/imp and expdp/impdp when it comes to importing HCC compressed data in Exadata?
If not, then follow me through two examples. This is on 22.214.171.124/126.96.36.199.1 but applies to all database releases you can have on Exadata. The task at hand is to export a table (which happens to be non-partitioned and HCC compressed for query high) and import it into a different user’s (more...)
I think I’ll create this as a sticky post as soon as I found out how this works in WordPress :) This is going to be a list of my public appearances in 2015.
Paris Oracle Meetup
The next time I’ll be speaking publicly is on April 15 in Paris at the Paris Oracle Meetup. Many thanks go to @Ycolin and @BertrandDrouvot for inviting me to my first ever presentation in France! I am very (more...)
In part 1 of the series I tried to explain (probably a bit too verbose when it came to session statistics) what the effect is of delayed block cleanout and buffered I/O. In the final example the “dirty” blocks on disk have been cleaned out in the buffer cache, greatly reducing the amount of work to be done when reading them.
Catching up with now, and direct path reads. You probably noticed that the migration (more...)