Infrastructure at your Service

Recovery Archives - Blog dbi services

Daniel Westermann

Can I do it with PostgreSQL? – 1 – Restore points

By | Database Administration & Monitoring | No Comments

When discussing with customers about PostgreSQL we often hear that they can do things in one database that they can not do in PostgreSQL. Most of the times this is not true and you actually can do it in PostgreSQL. Maybe not in exactly the same way but this is not surprising as PostgreSQL does implement features not in exactly the same way other vendors do. To start this series we’ll talk about restore points….

 
Read More
Daniel Westermann

The dbi services PostgreSQL reference architecture (2) – The community approach

By | Database Administration & Monitoring | No Comments

In the last post I looked at how dbi services designs a PostgreSQL architecture based on the products of EnterpriseDB. In this post I’ll look at the same questions but using pure community tools. If you do not need vendor support and do trust the community for providing help and fixes this is another way to go. And usually you can trust the community around PostgreSQL very well. The architecture itself is pretty much the…

 
Read More
Franck Pachot

Is CDB stable after one patchset and two PSU?

By | Database management, Oracle | 7 Comments

There has been the announce that non-CDB is deprecated, and the reaction that CDB is not yet stable. Well. Let’s talk about the major issue I’ve encountered. Multitenant is there for consolidation. What is the major requirement of consolidation? It’s availability. If you put all your databases into one server and managed by one instance, then you don’t expect a failure. When 12c was out (and even earlier as we are beta testers) – 12.1.0.1…

 
Read More
Franck Pachot

What’s the consequence of NOLOGGING loads?

By | Database management, Oracle | No Comments

When you load data in direct-path and have the NOLOGGING attribute set, you minimize redo generation, but you take the risk, in case of media recovery, to loose the data in the blocks that you’ve loaded. So you probably run a backup as soon as the load is done. But what happens if you have a crash, with media failure, before the backup is finish? I encountered recently the situation but – probably because of…

 
Read More
Franck Pachot

PDB media failure may cause the whole CDB to crash

By | Database management, Oracle | 3 Comments

Do you remember last year, when 12c arrived with multitenant, David Hueber warned us about the fact that a single PDB can, under certain conditions, generate a complete system downtime? We are beta testers and opened a SR for that. Now one year later the first patchset is out and obviously I checked if the issue was fixed. It’s a patchset afterall, which is expected to fix issues before than bringing new features. So the…

 
Read More
Franck Pachot

The consequences of NOLOGGING in Oracle

By | Database management, Oracle | No Comments

While answering to a question on Oracle forum about NOLOGGING consequences, I provided a test case that deserves a bit more explanation. Nologging operations are good to generate minimal redo on bulk operations (direct-path inserts, index creation/rebuild). But in case we have to restore a backup that was made before the nologging operation, we loose data. And even if we can accept that, we have some manual operations to do. Here is the full testcase….

 
Read More
Open source Team

Pgbarman : gestion de sauvegarde et récupération PostgreSQL

By | Hardware & Storage | No Comments

Fin 2012, j’ai présenté « pgbarman », une solution de sauvegarde et récupération pour PostgreSQL et décrit son installation. Pgbarman fournit un ensemble de commandes vous permettant la mise en œuvre de sauvegardes vers un serveur dédié. Le principal intérêt est à mon sens la gestion d’un catalogue de vos sauvegardes et la génération de commandes destinées à une reconstruction locale ou sur un serveur tiers. Je vais maintenant parler de la gestion des sauvegardes et décrire la…

 
Read More
David Hueber

Oracle 12c Backup & Recovery: What’s new?

By | Database management | One Comment

After months of waiting, Oracle Database 12c is finally available. In this posting, I am going to provide a summary of the new features of Oracle 12c in terms Backup and Recovery. Pluggable, what else? For sure, the most remarkable change in this brand new version is the Pluggable Database or so called Multitenant Database concept, which is a huge change in the whole RDBMS architecture. So what does it offers in terms of Backup…

 
Read More
David Hueber

Oracle 12c: Pluggable databases not that isolated

By | Database management | 12 Comments

As you probably know, the multitenant databases is the new feature of Oracle 12c to solve the dilema of applications segregation. Thanks to a multitenant container database, it allows to manage many databases as one taking advantage of resources consolidation. A perfect way to manage several applications in a single container. However are these plugglable databases that isolated as expected? Not exactly: As I will show in this posting, a single PDB can, under certain…

 
Read More