ORA-00600 [3631] recovering pluggable database after flashback database in Oracle 12c

I was trying to recreate the scenario where a 12c container database is flashed back to a SCN before the point that I recovered a pluggable database to using point in time recovery.

I got this ugly ORA-00600:

RMAN> recover pluggable database pdborcl;

Starting recover at 16-APR-14
using channel ORA_DISK_1

starting media recovery
media recovery failed
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of recover command at 04/16/2014 06:07:40
 (more...)

Using test prep software to prepare for 12c OCP upgrade exam

I got the newly available Kaplan test prep software for the Oracle 12c OCP upgrade exam.

I took the test in certification mode when I was tired at the end of the day some day last week and got 44% right – fail!  I usually wait until I get all the questions right before taking the real test so I have a ways to go.

The practice test software has been useful  in terms (more...)

Troubleshooting ADF ViewObject Range Paging Issues

ADF BC ViewObjects provide a very valuable mechanism to page through large data sets so that a user can navigate to a specific page in the results. Range Paging fetches and caches only the current page of rows in the ViewObject row cache (at the cost of another query execution) to retrieve each page of data. Range paging is very performing when your ViewObject has access to (hundreds of) thousands of database rows, and if (more...)

Performance live discussion on twitter, 12pm PST Tue April 15

Confio software is hosting a live discussion on twitter tomorrow Tuesday April 15 at 12pm PST on the subject of Oracle performance.

I’ll be online answering performance questions and have invited many other friends to participate. Some friends who’ve said they’ll be there are

Participation and tracking of the discussion can accomplished by either posting with and  following along with the #datachat  hashtag.

Get (more...)

An accusatory error message

I found this hilarious

SQL> startup
ORACLE instance started.

Total System Global Area 1469792256 bytes
Fixed Size                  2402776 bytes
Variable Size             536872488 bytes
Database Buffers          922746880 bytes
Redo Buffers                7770112 bytes
Database mounted.
ORA-19821: an intentionally corrupt log file was found

Really ? I intentionally corrupted my log file ?  I dont think so !

:-)


SQL injection

Another big public username and password leak…

http://o.canada.com/technology/bell-canada-security-breach-391451/

Some good reading on how it was done, and thus ensuring your code isn’t prone to SQL injection here:

http://www.troyhunt.com/2014/02/heres-how-bell-was-hacked-sql-injection.html


Pluggable database and restricted sessions

Once you get into pluggable database territory, you might need to check your usage of "alter system enable restricted session", because unless you’ve patched, there’s a little bug which lets you enable restricted session, but wont let you get out of it ! :-)

For example:

SQL> alter session set container = pdb12;
 
Session altered.
 
SQL> alter system enable restricted session;
 
System altered.
 
SQL> select logins from v$instance;
 
LOGINS
----------
RESTRICTED
 
SQL> alter system disable restricted  (more...)

OUGN 2014

I had the pleasure of being a guest of the Norwegian User Group for the second year in a row on their famous cruise conference at the start of April. For a relatively ‘small’ conference (around 300-400 people), the array of quality speakers the group manage to get is always astounding.  Martin Nash, Cary Millsap, Tim Hall, Bryn Llewellyn, Martin Bach, Jeff Smith, Doug Burns to name just a few.  I gave a (more...)

Maximum manageable storage in VMware versions

 

Maximum manageable storage per VM by ESX version

  • 4.1: 32TB (vmdk) / 120TB (RDM)
  • 5.0: 60TB (vmdk) / 3.75PB (RDM)
  • 5.1: 60TB (vmdk) / 3.75PB (RDM)
  • 5.5: 3.63PB (vmdk) / 3.75PB (RDM)

Note that the 60TB limit for 5.0 and 5.1 requires Update 1. Without this the limit is 24TB.

Exceeding the limits on ESX < 5.5 can result (more...)

Moving away from wordpress

I am sick of this advertisement on my site.

Therefor I am about to move most of my posts to

http://sysdba.ch/index.php/postlist

 

Thanks for following my blog for so long.

Lutz Hartmann


Good IT hygiene

Everybody knows they need good dental hygiene – daily brushing and flossing, regular checkups at the dentist. But many IT professionals don’t realize they need good IT hygiene as well – regular maintenance, security patches, etc.

If you don’t practice good IT hygiene, you will experience pain down the line. I’d like to help you avoid that – get in touch.

IOUG Collaborate 2014 presentations are online!

This is a small announcement that the slides of all of my four presentations for IOUG Collaborate 2014 are online in the ‘whitepapers and presentations’ section of this blog.


Toolmaking

My carpenter has been putting in a new floor in a room in my house, and I noticed that he makes some of his tools as he goes along.

It’s not that he doesn’t have a hammer and a cordless electric screwdriver. But every once in a while, he needs to move, align or support something in a way that his standard tools do not support. So he immediately builds an ad-hoc tool out of (more...)

Beyond Analytics: MODEL or MATCH_RECOGNIZE

Analytic functions are powerful and efficient, but sometimes they just aren’t enough. When you try analytics and they alone don’t solve the problem, it’s time to think about the MODEL clause – or upgrade to 12c and use MATCH_RECOGNIZE. All three can use partitions and ordering for simpler, more efficient processing. To illustrate, here’s a […]

Top 10 sessions from v$active_session_history

Description This query returns the top 10 sessions from v$active_session_history. The result is ordered by total resources consumed by the session including I/O, WAITS and CPU Be careful, this view is part of the diagnostic pack, you should not query this view if you don’t have license for it. top 10 sessions from v$active_session_history [crayon-5342de6f40853631954834/] [...]

The post Top 10 sessions from v$active_session_history appeared first on Oracle DBA Scripts and Articles (Montreal).

Down with Firefox

Warning: this post is not technical and it is not about Oracle. Brendan Eich recently resigned under pressure from his job as CEO of Mozilla, the makers of Firefox. The reason given was a campaign contribution that Mr. Eich made in 2008. The State of California has the “referendum”: a proposition is submitted to a […]

Two Adaptive Plans Join Methods Examples

Here is a zip of two examples I built as I’m learning about the new adaptive plans features of Oracle 12c: zip

The first example has the optimizer underestimate the number of rows and the adaptive plans feature switches the plan on the fly from nested loops to hash join.

In the second example the optimizer overestimates the number of rows and the adaptive plans feature switches the plan from merge join to nested loops.

(more...)

Time to wake up

This post is nothing more than a line in the sand, really.

After my post on “retiring” in November last year and then the one about working to network, as opposed to working to network just prior to 2013 year end, I have been very, very quiet. Well, I had things outside of Oracle and IT to do and they were more important to me. I’d say I have made a reasonable stab (more...)

ADF Runtime Diagnostics: Instrumenting your ADF Application – Part 2

In a series of blog articles I show how you can instrument your ADF Application key actions. Instrumenting gives visibility and insight of what is happening inside the ADF application and in the ADF framework (what methods and queries are executed, when and how often). These runtime diagnostics can be very effective in identifying and solving performance issues. This enables developers to diagnose and solve performance problems at an early stage and to build an efficient, (more...)

Norway bound

I cant wait to get to Norway again for this year’s OUGN conference.

If you’re in Europe…this should be on your must-attend list every year.

It’s awesome fun.

I’ll be talking about Clone DB, Optimizer Stats and Analystics in SQL

http://ougnvarseminar2014.sched.org/