Everything our consultants learn while running databases for customers: Oracle, PostgreSQL, SQL Server, MySQL, MariaDB, MongoDB and Delphix. Expect hands-on posts about installation, day-to-day administration, backup and recovery, performance tuning, replication and upgrades.
A lot of people ask me about the different versions of SQL Server Integration Services and packages. I create rapidly this little table to summarize it: With SQL Server 2008 and 2008 R2, the SSIS version is the same than SQL Server Integration Services 10.0. With SQL Server 2005, the SSIS version is not contained in the service name. To…
By Franck Pachot . You don’t want to reload the datawarehouse database every night. And you may want to have it refreshed more often, in real-time during the day. There is another reason to capture all changes from the operational database: you want the history of all updates and not only the current value. This is why you use Change…
We discovered a strange behavior in the Alert Log when the Fast Recovery Area (FRA) is full and the database wants to write something inside it (for example an archivelog). This case concern Oracle 11.2.0.3 databases and higher. Here is a demo with a 12c database (12.1.0.2) : First, to reproduce the behavior, I set a very small size to the FRA :…
How many applications do you know that need to define a validity of a row? And how many of these do that by adding two columns: valid_from and valid_to or similar column names? Well, in PostgreSQL (you already suspect it 🙂 ) there is much more elegant way to do that. PostgreSQL knows the concept of range types. Several of…
During a copy of a database from an environment to another (from Production to pre-production for instance), people usually don’t changed the logical name of the data or log files when they rename the database and the physical file names. In my test environment, I create 2 copies of AdventureWorks and you can see that the logical name is the…
By Franck Pachot . My first trial was not very good because I had access to Schema as a Service only. Which is not new. But Oracle Cloud Services is becoming now a reality, available for trial and available for general availability. Let’s see now how to use Database as a Service. Creation My goal here is to see what…
By Franck Pachot . Yes, the topics for the OCM 12c upgrade are online and I’m already looking at the topics. I’m talking about the ‘Configure the Resource Manager’ one here. Configuring Resource Manager in commandline is not easy. At the OCM exam you can do things faster when you have a GUI. Of course, you need to know where…
By Franck Pachot . In the part I we have seen the properties that are imported when you add a database to the configuration, and which are then managed by the broker. Now we will list the properties that are managed by the broker, but whose default value is not imported from the instance parameters. LogXpt properties Here are the…
By Franck Pachot . When I passed the OCM 11g exam, I had to prepare the ‘Manage Materialized Views to improve rewrite’ topic. Now that I’m preparing the 12c upgrade I checked quickly what I’ve prepared… and it doesn’t work. This post is about query rewrite, a bug in 12c, how to understand why it doesn’t rewrite, and how rewrite…
By Franck Pachot . When you are using the DataGuard Broker, you should always use the broker (with DGMGRL or OEM) to change the parameters that are managed, rather than changing them with ALTER SYSTEM. But do you know which parameters are concerned? I’ve divided the parameters in two parts. All are set by the broker, but only some of…
As you might know PostgreSQL 9.5 is currently in alpha 2. One of the new features will be the possibility to import foreign schemas. Having this it is no longer required to create all the foreign tables which saves a lot of work. Setting up oracle_fdw was done in exactly the same way as in the previous post. Make sure…
Hi folks, Some of you probably already got error 1040 by playing with sysbench for instance and multiplying the number of MySQL threads. Documentation and blogs usually simply state that you have to increase the number of max_connections and the open files limit. If you tried and you didn’t succeed this blog is for you. Despite the following entries in…
