Blog posts

Oracle multi-tenant: PDB scope parameters and where you can see them.

Working with Oracle multi-tenant architecture gives us some obvious benefits but also some challenges. What if we want to change a system parameter but only for a certain pluggable database (PDB) and keep it default for all others? Starting from 12.1 Oracle provides the ability to modify parameters on PDB level. If you look to a reference documentation for database parameters it states clearly whether it can be applied on CDB level or not. And with every new release we have more and more parameters which can be changed on PDB level. It has grown from 185 for 12.1.0.2 to 194 on 19.7.0.0.

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Migrating a new PDB to the existing 19c DataGuard on ExaCC.

We’ve already discussed  how to migrate databases from a standalone 12.2 database to a pluggable database (PDB) in a 19c container in the Oracle cloud. But what if the target container database (CDB)  is already part of a Data Guard configuration and has several PDB in it? I will try to go through the main steps on how to do that without breaking the replication. 

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Moving Oracle database to the cloud. 12.2 standalone to 19C RAC PDB.

I see more and more Oracle databases are moving to the public cloud or to a hybrid cloud solution. Depending on the platform, size and used options it could be a different path but the general approach boils down to three main options – Oracle RMAN backup and restore, Oracle Data Guard or Oracle Data Pump with or without transportable tablespaces. Here I want to share our approach for migration from 12.2 standalone database to 19c RAC container as PDB in the Oracle Cloud Infrastructure (OCI). 

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Oracle Zero Downtime Migration troubleshooting.

The Oracle Zero Downtime Migration (ZDM)  tool has been created to help with Oracle databases migrations. It saves time and automates many tasks. The saved effort is getting bigger and accumulates on scale when you need to move multiple databases. Behind the scenes it uses the very well known Oracle Data Guard. As a result you have good solid technology on the basis but at the same time limited to what the DataGuard can do and what it cannot. All details and documentation are available here.  The tool works fine when all prerequisites are met but when you hit an issue you need to dig in and troubleshoot. Here I will try to share some experience with the ZDM troubleshooting. Please note that the information in the blog is actual for the 19.2 version of ZDM and it is possible that the behaviour will be different in the future versions.

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Cloud and how it might help at difficult times.

The recent changes caused by the virus and economic meltdown affected almost everybody in the world. We are all now going through a difficult period of our history, and when many companies are struggling to survive, the other thrive and boost production. In such volatile environment, it becomes more and more important to be able to adapt the IT environment to immediate business needs quickly.

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Exadata Cloud at Customer – number of active CPUs and adding a new database.

Let’s imagine a typical working day, and you are getting a request to add a new database to your Exadata Cloud at Customer (ExaCC). If you are not familiar with the product, you can read about it in detail here. In short, it is an Exadata machine with a cloud interface, something like Oracle Exadata Cloud Service, but with the hardware installed in your datacenter. 

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Desktop in the cloud? Easy.

This is a difficult time for everyone, even if you are used to working most of the time from home, airport, cafe, or any other place. The problem is not only how good you are managing your time but sometimes in network reliability and throughput. When so many people work from home, and so many kids are trying to watch streaming services at the same time, your home network might be under severe pressure. In such a case, a remotely hosted desktop product could be the solution.

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Is Oracle cloud only for Oracle?

Several days ago, discussing public cloud solutions and competition between different providers, one of the people mentioned that Oracle Cloud is just for Oracle products. At the same time, AWS and Azure are more vendor agnostic. I was a bit surprised by that statement but it appeared that several other people shared the same view. I decided to write the blog and show what options Oracle Cloud Infrastructure (OCI) has for different workloads.

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Oracle OCI Database service storage allocation.

Today I would like to discuss the block storage allocation in a VM based Oracle DBCS system. Several times in different conversations it was mentioned that the block storage will be allocated with triple redundancy on the ASM level. Let’s check it out.

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Linux LVM for Oracle Database on OCI

Oracle Database as a service (DBCS) on Oracle Cloud Infrastructure (OCI) had been traditionally built based on Oracle Grid Infrastructure with ASM as the main storage layer for the database, however Oracle recently has started to offer a Linux LVM as the storage alternative. Which option is the better alternative? Let’s review some of the differences between the two options.

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