Infrastructure at your Service

Category Archives: Database management

Clemens Bleile

Workaround for bug 19566227/20563128 doing Cross Platform Migration (MOS Note 1389592.1)

By | Database Administration & Monitoring, Database management | One Comment

In a project I have to move an Oracle 11.2.0.4-DB (around 7TB in size) from Sparc Solaris (called Source in the remainder of this Blog) to Linux x86-64 (called Target in the remainder of the Blog). I.e. a platform migration from Big Endian to Little Endian. A good method to do that is described in My Oracle Support Note 1389592.1: 11G – Reduce Transportable Tablespace Downtime using Cross Platform Incremental Backup Basically I copy the…

 
Read More
Franck Pachot

random “ORA-01017: invalid username/password” in 12cR2

By | Database management | 4 Comments

Since 12cR2 is out, we give our 12c new feature workshop with hands-on exercises on 12.1 and 12.2 releases. When I gave it last month, I had a small problem when doing demos: sometimes the connections as sysdba failed with “ORA-01017: invalid username/password”. It was at random, about one every 5 login attempts and I was sure that the password did not change. As I give another of this training next week, I tried to…

 
Read More
Franck Pachot

12cR2 Cross-container DML – insert into container()

By | Database management | No Comments

Multitenant has been introduced in 12.1.0.1 with the goal to share resources but isolate data. However, having all PDBs in the same root may be convenient to manipulate data in multiple PDBs. In the first patchset, 12.1.0.2, a way to query cross-container has been introduced for the CDB administrator to see data in other containers. In the second release, 12.2.0.1, this goes further with the introduction of Application Containers and cross-PDB DML. Currently, not all…

 
Read More
Joël Cattin

Oracle 12cR2 : Optimizer Statistics Advisor

By | Database Administration & Monitoring, Database management, Development & Performance | No Comments

The Optimizer Statistics Advisor is a new Advisor in Oracle 12.2. The goal of this Advisor is to check the way you gather the statistics on your database, and depending on what is found, it will makes some recommendations on how you can improve the statistics gathering strategy in order to provide more efficient statistics to the CBO. This Advisor is also able to generate remediation scripts to apply the statistics gathering “best practices”. The…

 
Read More
Franck Pachot

12c nologging and Data Guard

By | Database management | 3 Comments

The title sounds weird because Data Guard synchronisation is based on the redo stream, so it makes no sense to do nologging operations on the primary. And this is the reason why we set FORCE LOGGING on a Data Guard configuration. However, to lower the downtime of a migration done with Data Pump, you may want to import with minimal logging and then re-synchronize the standby. This post is about the re-synchronisation in 12.1  

 
Read More
Franck Pachot

Listener and Virtual IP

By | Database management | No Comments

When you configure a standby database, you want the application to transparently connect to the primary database, wherever it is. That’s the role of Transparent Application Failover, but this requires configuration on the client side. If you can’t configure TAF, you can use a virtual IP address. But then the question is how to configure the listener.ora to handle connections to this VIP.  

 
Read More
Franck Pachot

12cR2 RMAN> REPAIR

By | Database management | One Comment

Do you know the RMAN Recovery advisor? It detects the problems, and then you: RMAN> list failure; RMAN> advise failure; RMAN> repair failure; You need to have a failure detected. You can run Health Check if it was not detected automatically (see https://blog.dbi-services.com/oracle-12c-rman-list-failure-does-not-show-any-failure-even-if-there-is-one/). In 12.2 you can run the repair directly, by specifying what you want to repair.  

 
Read More