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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:

 

Multiple invisible indexes on the same column in #Oracle 12c

After invisible indexes got introduced in 11g, they have now been enhanced in 12c: You can have multiple indexes on the same set of columns with that feature. Why would you want to use that? Actually, this is always the first question I ask when I see a new feature – sometimes it’s really hard to answer :-)

Here, a plausible use case could be that you expect a new index on the same column to be an improvement over the existing old index, but you are not 100% sure. So instead of just dropping the old index, you make it invisible first to see the outcome:

 

AUDIT_SYS_OPERATIONS defaults to TRUE in #Oracle 12c

A small but remarkable change in Oracle Database 12c is the default value of AUDIT_SYS_OPERATIONS has changed to TRUE now. In other words, all actions done by the superuser sys are being audited now by default!

Become an #Oracle Certified Expert for Data Guard!

It is with great pride that I can announce a new certification being available – Oracle Database 12c: Data Guard Administration.

We wanted this for years and finally got it now, after having put much effort and expertise into the development of the exam. It is presently in beta and offered with a discount. Come and get it!

Kostenlose Webinare zur neuen #Oracle Datenbankversion: #12cjetzt

#12cjetzt

Hochkarätige Referenten zum Thema Oracle Database 12c – Jetzt!

Wie und warum Sie jetzt auf 12c kommen sollten erläutern wir in sieben Webinaren von je einer Stunde Dauer. Die Webinare finden an jeweils verschiedenen Tagen statt, beginnend am 11. August, wo Mike Dietrich zum Thema Upgrade (natürlich) vortragen wird.

Einfach anmelden und bequem und kostenlos informieren – das ist doch ein unschlagbares Angebot, oder? Finde ich auch :-)