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12c New Features

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!

Kostenlose Webinare zur neuen #Oracle Datenbankversion: #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 :-)

Transport Tablespace using RMAN Backupsets in #Oracle 12c

Using backupsets for Transportable Tablespaces reduces the volume of data you need to ship to the destination database. See how that works:

RMAN TTS on the source database

RMAN TTS on the source database

The tablespace is made READ ONLY before the new BACKUP FOR TRANSPORT command is done. At this point, you can also convert the platform and the endian format if required. Then on the destination site:

Multisection Backup for Image Copies

A nice Oracle Database 12c New Feature enhances the multisection backup, introduced in 11g: You can use it now for image copies also!

Multisection Backup with Image Copy

Multisection Backup with Image Copy

What happens to the Standby when you move a datafile on the Primary?

In 12c, we have introduced online datafile movement as a new feature. Now does that impact an existing standby database? I got asked that yesterday during an online webinar. My answer was that I expect no impact at all on the standby database since redo apply doesn’t care about the physical placement of the datafile on the primary. But I added also that this is just an educated guess because I didn’t test that yet. Now I did:

New 12c Default: Controlfile Autobackup On – But only for Multitenant

This a a little discovery from my present Oracle Database 12c New Features course in Copenhagen: The default setting for Controlfile Autobackup has changed to ON – but only for Multitenant, apparently:

Common Roles get copied upon plug-in with #Oracle Multitenant

What happens when you unplug a pluggable database that has local users who have been granted common roles? They get copied upon plug-in of the PDB to the target container database!

Before Unplug of the PDBThe picture above shows the situation before the unplug command. It has been implemented with these commands:


Restore datafile from service: A cool #Oracle 12c Feature

You can restore a datafile directly from a physical standby database to the primary. Over the network. With compressed backupsets. How cool is that?

Here’s a demo from my present class Oracle Database 12c: Data Guard Administration. prima is the primary database on host01, physt is a physical standby database on host03. There is an Oracle Net configuration on both hosts that enable host01 to tnsping physt and host03 to tnsping prima


Data Guard 12c New Features: Far Sync & Real-Time Cascade

UKOUG Oracle Scene has published my article about two exciting Data Guard 12c New Features:

Far Sync Instance enables Zero-Data-Loss across large distance

Hope you find it useful :-)