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Happy New Year 2016!

Another year has passed. I take the opportunity to thank you for visiting and to wish you a Happy New Year 2016!

Happy New Year 2016!

In case you didn’t recognize: That is supposed to look like fireworks, The Oracle Instructor style ;-)

2015 was a great year for uhesse.com with 345,000+ views and the crossing of the one million hits threshold. Top countries with more than 4,000 views in 2015 were

Visitors 2015

Upgrade a Pluggable Database in #Oracle 12c

This is how an upgrade with pluggable databases looks conceptually:
You have two multitenant databases from different versions in place. Preferably they share the same storage, which allows to do the upgrade without having to move any datafiles
Initial state

You unplug the pluggable database from the first multitenant database, then you drop it. That is a fast logical operation that does not delete any files

unplug drop

Next step is to plug in the pluggable database into the multitenant database from the higher version

Full Database Caching in #Oracle 12c

If your Oracle Database fits into the buffer cache, we will put all segments into it now upon access – no more direct reads:

SQL> connect / as sysdba
Connected.
SQL> select banner from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
PL/SQL Release 12.1.0.2.0 - Production
CORE	12.1.0.2.0	Production
TNS for Linux: Version 12.1.0.2.0 - Production
NLSRTL Version 12.1.0.2.0 - Production

SQL> select sum(bytes)/1024/1024 as mb from v$datafile;

	MB
----------
      1424

SQL> select current_size from v$buffer_pool;

CURRENT_SIZE
------------
	1872

The requirements are met here, I don’t need to force anything:

DOAG annual conference 2015 – great as always!

Another annual DOAG conference has passed, and I can only say the very best about it: Perfectly organized, large and modern location, impressive list of well known speakers and over 2100 attendees – wow!

DOAG_2015

My presentation Best of RMAN was scheduled at the first slot on the first day, so I was a bit concerned whether many people would attend that early. It turned out that the room got so full that I was asked by the organizers to deliver the same talk again next day – which I happily did, again with a packed room :-)

Auto optimizer stats after CTAS or direct loads in #Oracle 12c

Less famous 12c New Feature: If you do Create Table As Select (CTAS) or a direct load into an empty table, we will automatically collect optimizer statistics:

Four members of our team are in the Leadership Circle!

Oracle University Leadership Circle Q1FY16

The recipients of the Oracle University Leadership Circle Quarter 1 Fiscal Year 2016 have just been announced. That is a corporate award for the best instructors worldwide according to customer feedback. Not less than four (!) come from our small team of 14 instructors:

Leadership Circle Recipients Q1FY16

Yes, we have a great team – supported by a great manager: Thank you, Richard! Congratulations to everyone in the circle this time, I feel honored to be listed together with you!

RMAN old feature: Restore datafile without backup

Say I have created a new tablespace recently and did not yet take a backup of the datafile. Now I lose that datafile. Dilemma? No, because I can do an ALTER DATABASE CREATE DATAFILE. Sounds complex? Well even if I wouldn’t be aware of that possibility, a simple RMAN restore will work – as if there were a backup:

#Oracle Learning Streams – Have a look!

Oracle University has introduced a new format that suits the way many learn today: Oracle Learning Streams

Oracle Learning Streams

Although I do not expect that this format will replace classroom training, I consider it a great enhancement – coming with a price like most good things…

As you can see, I’m happy to contribute to it in my area of expertise: You can find me here in the Database Stream.

FASTSYNC Redo Transport for Data Guard in #Oracle 12c

FASTSYNC is a new LogXptMode for Data Guard in 12c. It enables Maximum Availability protection mode at larger distances with less performance impact than LogXptMode SYNC has had before. The old SYNC behavior looks like this:

LogXptMode=SYNC

LogXptMode=SYNC

The point is that we need to wait for two acknowledgements by RFS (got it & wrote it) before we can write the redo entry locally and get the transaction committed. This may slow down the speed of transactions on the Primary, especially with long distances. Now to the new feature:

Less Performance Impact with Unified Auditing in #Oracle 12c

There is a new auditing architecture in place with Oracle Database 12c, called Unified Auditing. Why would you want to use it? Because it has significantly less performance impact than the old approach. We buffer now audit records in the SGA and write them asynchronously to disk, that’s the trick.

Other benefits of the new approach are that we have now one centralized way (and one syntax also) to deal with all the various auditing features that have been introduced over time, like Fine Grained Auditing etc. But the key improvement in my opinion is the reduced performance impact, because that was often hurting customers in the past. Let’s see it in action! First, I will record a baseline without any auditing: