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January 2014

OTN Yathra 2014 : See you there!

In November I wrote a post about my possible inclusion in the OTN Yathra 2014 tour. That has been confirmed now, so I’m representing OTN and the Oracle ACE Program at all the cities in the tour.

OUG Ireland 2014 : I’m going to be there. Are you?

Earlier in the week I got confirmation I have two papers selected for OUG Ireland 2014.

  • PL/SQL : Stop Making The Same Performance Mistakes
  • An Oracle DBA’s Guide to WebLogic Server

You can see the full agenda here.

I got on the net to check flight prices and Ryanair were doing a round trip for £13. The booking fee on the travel site I used was more then the flight costs, so the total flight costs came to £30. :) Needless to say I booked them straight away, so I will be there representing OTN and the Oracle ACE Program.

ORA-65131 grrrr

So…the future is container databases ?

Cool ! I’ll create all my databases as container databases….I’m so happy….until

ERROR at line 1:
ORA-65131: The feature Flashback Data Archive  is not supported in a pluggable database.

It is documented but seriously….that’s not so flash :-)

Man…I really really like this :-)

Yeah yeah, you can argue with me about backward compatibility, but I’m so glad someone snuck this into 12c…


SQL> grant resource, connect to demo identified by demo;

Grant succeeded.

SQL> select privilege
  2  from   dba_sys_privs
  3  where  grantee = 'DEMO';



SQL> grant resource, connect to demo identified by demo;

Grant succeeded.

SQL> select privilege
  2  from   dba_sys_privs
  3  where  grantee = 'DEMO';

no rows selected

EM12c Adding Targets and Keeping it Clean

I often have folks ask me for assistance when target discovery isn’t successful.  The following is from a client’s environment that shows just how important it is to ensure your server environment is kept pristine.

Bitmap question

If you know anything about bitmap indexes you probably know that a single entry in a bitmap index takes the form (key_value, starting rowid, ending rowid, BBC compressed bit string). So an entry covers a single value for a column over a range of rowids  in the table, and the string of bits for that (notional) range is reduce to a minimum by a compression mechanism that eliminate repeated zeros in multiples of 8.

So here’s a question – to which I don’t know the answer, although you may be surprised when you try to find it:

If you have a very large table and in one of its columns the first row and the last row (and no others) hold the value 0 (say) and you create a bitmap index on this column, what’s the largest number of rows you could have in the table before Oracle would HAVE to create two index entries in order to cover both rows ?


The recent public speaking posts have made me very aware of other people’s behaviour at the moment. I’m sure I will soon revert back to my self-obsessed state, but for now I’m riding this wave. :) Something happened a few days ago that I thought was very interesting…

I took my 12 year old nephew to a local store so he could buy something. We both waited in the queue, him holding the items. He walked up to the counter, placed the items down and stood, money in hand, waiting for the items to be passed through the checkout. The checkout lady looked at me and said, “Do you want a bag?”. I tilted my head towards my nephew in a “why don’t you ask him?” manner, which she ignored, so I conceded and said to my nephew, “Do you think we need one?”

Virtual Columns

This is just a temporary note to let people know I’ve added an update to my Virtual Stats article, highlighting a possible performance threat when you gather stats.

I’ll be deleting this note in a couple of days, so I’ve disabled comments and pingbacks



Database as a Service

Concept of Hand with Electronic Fingerprints

by Chris Fuller and Kyle Hailey

To improve infrastructure and DBMS software utilization, and to drive greater IT operational productivity, companies are implementing internal DaaS capabilities to address their database needs.

Screen Shot 2014-01-15 at 11.17.58 AM


Applying GI PSU in the lab

In my previous posts about the first RAC Grid Infrastructure Patchset I document a few issues I encountered that were worth noting. But where things work as advertised I am more than happy to document it too. In a way, the January 2014 GI PSU works as you’d hope it would (at least in my lab for my 2 node cluster). Well-almost: if you have a non 12.1 database in your environment you might encounter this.

UPDATE: You might want review some additional information with regards to datapatch.

Admittedly it’s taken from an Oracle Restart (i.e. non cluster) environment but I can’t see this not happening in RAC: