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12c New Features

Fast-Start Failover for Maximum Protection in #Oracle 12c

Fast-Start Failover is supported with Maximum Protection in 12cR2. Also Multiple Observers can now monitor the same Data Guard Configuration simultaneously. I will show both in this article. Starting with a (Multitenant) Primary in Maximum Protection mode with two Standby Databases. It is still not recommended to have the highest protection mode configured with only one standby. So this is my starting point:

DGMGRL> show configuration;

Configuration - myconf

Protection Mode: MaxProtection
Members:
cdb1 - Primary database
cdb1sb - Physical standby database
cdb1sb2 - Physical standby database

Fast-Start Failover: DISABLED

Configuration Status:
SUCCESS (status updated 57 seconds ago)

All three databases have flashback turned on. I want to have a setup like this in the end:

Auto Sync for Password Files in #Oracle 12c Data Guard

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Real-Time Materialized Views in #Oracle 12c

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How to move Partitions ONLINE and make them READ ONLY in #Oracle 12c

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Hot cloning and refreshing PDBs in #Oracle 12cR2

Hot cloning PDBs is new in 12.2, so you don’t have to put the source PDB into READ ONLY mode before the cloning if you have it in local undo mode. I suppose shared undo mode will become very unpopular. Another 12.2 New Feature is the option to clone a PDB that can be refreshed from the source PDB. I will show both features with this article, but you may of course do hot cloning without a later refresh. In this case, just leave out the REFRESH MANUAL clause and you don’t have to OPEN READ ONLY the cloned PDB afterwards. On a high level, what I demonstrate is this:

How Partial Indexing helps you save space in #Oracle 12c

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Over time certain partitions may become less popular. In 12c, you don’t have to index these partitions anymore! This can save huge amounts of space and is one of the best 12c New Features in my opinion. Really a big deal if you are working with range partitioned tables where the phenomenon of old ranges becoming unpopular is very common. Let’s have a look, first at the problem:

How to speed up Data Pump Import by suppressing redo generation in #Oracle 12c

With your database in archive log mode, a Data Pump Import may be severely slowed down by the writing of much redo into online logs and the the generation of many archive logs. A 12c New Feature enables you to avoid that slow down by suppressing redo generation for the import only. You can keep the database in archive log mode the whole time. Let’s see that in action!

First without the new feature:

How to safeguard against malicious developers in #Oracle 12c

AUTHID_CURRENT_USER can be misused by developers. The new object privilege INHERIT PRIVILEGES ON was introduced in 12c to prevent that. I start with a demo to explain the problem that the new features solves. The playground:

How to do PDB PITR in #Oracle 12c

A logical error happened in one Pluggable Database. A PDB Point-In-Time-Recovery rewinds it while the others remain available and stay as they are.

Logical error in PDB2

Logical error in PDB2