What is a “RAC Battle”?

RAC Battle [ræk ˈbæt̬l̩]

A “RAC Battle” is a format of presenting technology – two experts, battling against each other on pros and cons of Oracle Real Application Cluster. Björn Rost (Oracle ACE Director) and Martin Klier (Oracle ACE)

Björn Rost  Martin Klier

will fight

Wednesday November 18th, 2015
11 am
Nürnberg CCN (DOAG Konferenz 2015)
Room St. Petersburg

Who will be pro? Who will be con? We don’t know, we will decide by lot in front of the audience.

Be there, to see a technology event at its best in rounds, with no strings attached. Are you afraid of violence? Stay calm, Johannes Ahrends (Oracle ACE) will be the referee to avoid bloodshed.

Johannes Ahrends

Here’s the official RAC Battle link from DOAG.

Oracle Database 11.2 Extended Support Waived

As announced today, Oracle waived the Extended Support for the period of February 2015 until May 2017.


See the paper with details here.

Oracle 12c in practice – customer report in Cologne #12cjetzt

From Beta to Production – Oracle 12c at TGW
In October, I’ll speak at the Oracle #12jetzt (#12cnow) symposium in Köln (Cologne) about the introduction of 12c as standard palttform at our ISV customer TGW Software Services.

12c jetzt Symposium Header

I had the privilege to continuously working on the 12c product evaluation and introduction from availability of 12c beta2 until today. My company, Performing Databases, played the key role for creating and developing the guidelines of operation, configuration and licensing. My example will be the “new” development environment, to show the first steps of the project. The highlight of the talk will be the report about our migration from 9i to 12c at S.Spitz GmbH, the biggest food vendor in Austria.

October 15th
approx. 11am

Hyatt Regency Köln
Kennedy-Ufer 2A
50679 Köln

Please see the agenda here.

Link to the presentation here.

Oracle dbms_workload_repository.awr_global_report_text fails with ORA-06553 PLS-307

My last post was about generating AWR reports from SQL – not a very complicated case. “But” – little word, big meaning. And suddenly we get a strange error message.

In my example, I was especially interested in a Real Application Cluster’s “global” report. The subprogram call for that purpose is dbms_workload_repository.awr_global_report_text(), accepting the DBID, begin snapshot, end snapshot, an option field, and, l_inst_num for the instance number. Regardign the latter, Oracle documentation says: “List of instance numbers to be included in report. If set to NULL, all instances for which begin and end snapshots are available …”

But when I did that, I got an error that felt strange to me:

ORA-06553: PLS-307: too many declarations of ‘AWR_GLOBAL_REPORT_TEXT’ match this call

Read more…

How to create an Oracle AWR report with SQL and PL/SQL

AWR is a great tool (but needs diagnostics pack). It can create very useful reports for performace analysis over a given period. Most people will pull the AWR Report  from the OS level, with ‘@?/rdbms/admin/awrrpt.sql” (or one of the other scripts there). But sometime it’s not possible to access a database server’s OS level, or gain permission to do so. So we also can create the whole bunch of possible AWR and ASH reports from SQL level, too. We can have it in text or HTML, it’s just a matter of personal taste. I always preferred the text version, but there are many facts pro HTML. Anyway, here is my cheat sheet how to do it, and the difference in RAC.

What we have to know

Our database ID (DBID):

select dbid 
  from v$database;

The period we are interested in, spoken in snapshot IDs:

select /*+ FIRST_ROWS */ * 
  order by snap_id desc, instance_number desc;

Retrieving the report

SELECT output
FROM TABLE (dbms_workload_repository.awr_report_text(

Read more…

Oracle 12c RMAN delete obsolete behaves interactively in DBMS_SCHEDULER job type BACKUP_SCRIPT


In Oracle Database 12c, we have the long-missed feature of DBMS_SCHEDULER job type “BACKUP_SCRIPT”, that allows us to create backup jobs without creating them as an OS file, and without need for a wrapper script that’s called by a job type EXECUTABLE (as we usually did that in the last years).

Sometimes we also have to use the RMAN command “delete obsolete” to get rid of unneeded backup pieces. When executed interactively, it comes back with the question “Do you really want to delete the above objects (enter YES or NO)?”. But when running from a script, it just deletes:

Deleting the following obsolete backups and copies:
Type                 Key    Completion Time    Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set           67     30-JUN-15 
Backup Piece         67     30-JUN-15          +ORAFRA/...nnndf...
deleted backup piece
backup piece handle=+ORAFRA/...nnndf0_tag...
Deleted 1 object
Recovery Manager complete.


Strange is, that when using it within a DBMS_SCHEDULER job type BACKUP_SCRIPT, “delete obsolete” thinks it was running interactively, and the scheduler seems to compensate it, by simply answering “NO” – what leaves us with a growing number of old backup pieces!
(Taken from v$rman_output):

Deleting the following obsolete backups and copies:
Type                 Key    Completion Time    Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set           61     30-JUN-15
Backup Piece         61     30-JUN-15          +ORAFRA/.../nnndf0_tag....
RMAN-06546 Error occurred getting response - assuming NO response

DOAG Database Conference 2015 begins #DOAGDB15

It’s time! June 16th, the DOAG Database Conference takes place in Düsseldorf, Van Der Valk Airport Hotel. Twenty-two specialized talks about Oracle Database, Replication, Tools and Security promise a great techie-day. See the schedule of lectures here.


I’m looking forward to seeing you there, having great corner talks about Oracle, life and lemons, tweeting with hashtag #DOAGDB15 and enjoying this great environment the hotel provides.

I’m also glad and honoured to be on the list of speakers: “Oracle Core for Beginners: In-Memory Column Store” at 11am.

Take care and see you tomorrow!

DOAG BI Conference: Oracle Core (for Beginners): In-Memory Column Store


On Thursday, April 23rd I’m speaking at DOAG BI 2015, the leading Oracle Business Intelligence Conference in Germany. (#DOAGBI15)

My contribution is: “Oracle Core für Einsteiger: In-Memory Columns Store”. The lecture will show, how the Oracle Database In-Memory option works “under the hood”, and how it is used to the best effect.

Please find the presentation here for download.


Looking forward to seeing you there, or discussing the presentation in the comments.


Chemnitzer Linux Tage 2015

Last weekend, I had the chance to attend the Linux Days Chemnitz. It’s an annual meeting of the German Linux family with roundabout 2,500 attendees and a FANTASTIC atmosphere. It was two days of hearing tech talks, enjoying rich nerd content and talkin’ shop.


Great atmosphere in the Great Hall


Great entrance gift: “Free Culture” by Lawrence Lessig. Thank you very much!

Read more…

Oracle ACE

I feel VERY proud, honoured and grateful, that Oracle awarded me with the Oracle ACE in December 2014. The Oracle ACE program is a community reward, and encourages us to participate, enrich, promote and organise Oracle community events.


When speaking about the community, first of all I’d like to highlight my Oracle User Group of Germany, the DOAG (Deutsche Oracle Anwendergruppe). They are doing lots of nice, and educational things, lifting the fog, and practicing free and self-assured community work. Helping to spread this in our region, at conferences and events, is a pleasure. I’m very proud to be part of this great team.

A little less, due to the geographical distance, but with very similar motivation and experience, I feel connected and involved with the U.S. pendant IOUG (Independent Oracle Users Group). They are open for the international crowd, and it simply feels good to be there.

And I want to say thank you to three people, for all they do, think and say about me. These very special folks are Björn, Craig and Dietmar. I’m proud to call you friends.

My Oracle ACE program shipment just arrived today.

My Oracle ACE program shipment just arrived today.

Just in case somebody cares, here’s my Oracle ACE profile.

I hope to keep up the level, and will continuously try hard to find the time to give back knowledge to the community.

Martin Klier