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.
Some days ago EnterpriseDB released a new version of its EDB Failover Manager which brings one feature that really sounds great: “Controlled switchover and switchback for easier maintenance and disaster recovery tests”. This is exactly what you want when you are used to operate Oracle DataGuard. Switching back and forward as you like without caring much about the old master.…
By Franck Pachot . Database on ACFS is a long story. At first, the main reason for ASM was to bypass a filesystem layer that is not required by the database. ACFS was for the non-database files that had to be accessed by all cluster nodes. But then, storage vendors and other providers came with snapshots, compression and thin provisioning…
Ausgangslage Ein Kunde hat mich kürzlich angefragt, wie am effizientesten alle Kernel Tuning Parameter für Oracle bei Red Hat 7 konfiguriert werden können. Daraus habe ich untersucht welche Möglichkeiten es gibt, ausser dem seit langer Zeit bekannten /etc/sysctl.conf. Bei dieser Analyse führt der Weg natürlich über tuned. Dieser Dienst erlaubt es Profile zu definieren welche ein ganzes Set von Kernel Tuningparametern…
By Franck Pachot . Here are the details about an execution plan screenshot I’ve tweeted recently because the numbers looked odd. It’s not a big problem, or maybe not a problem at all. Just something surprising. I don’t like when the numbers don’t match and then I try to reproduce and get an explanation, just to be sure there is…
Objective of the document is to describe how to start manually with command lines a development project, from an existing GIT repository. Usage of GIT protocol for software development empowers projects team management. It is intended to ease source code management in terms of versioning, branching and sharing between all team members. GIT platform Architecture GIT is a distributed…
Today, especially in the Pharma and Banking sectors, sooner or later you will be faced with the requirement of auditing. Detailed requirements will vary but usually at least tracking logons to the database is a must. Some companies need more information to pass their internal audits such as: Who created which objects, who fired which sql against the database, who…
By Mouhamadou Diaw In this article we will talk about a nice feature Row Level Security on PostgreSQL. We are using EDB Postgres Advanced Server 9.5. Suppose that I am a team manager and that employee bonus are stored in a table Bonus. I want that each employee can see only data related to him and not data for other. How Can…
By Franck Pachot . Today I was doing a hard parse storm post-mortem analysis. One hypothesis was rolling invalidation causing invalidation, but figures didn’t match. I often reproduce the hypothesis to check the numbers to be sure I interpret them correctly. Especially the timestamps in V$SQL_SHARED_CURSOR.REASON. And as it may help others (including myself in the future) I share the…
Do you need the Oracle sample schemas to do a quick test or demonstration? And, as always, you did not install the sample schemas when you did the setup of your environment? The probably fastest way to get them installed is to download them from github. Installation instructions are there as well. Have fun …
By Franck Pachot . If you have read my latest blog posts, you know I’ve measured IOPS with SLOB to estimate ACFS overhead on a fast storage. This blog is about something I learned after wasting one hour on the result. Here is how I did my tests: Create a SLOB database in ACFS Run SLOB PIO tests and tag…
Today at one of our GoldenGate customers we were faced with the following requirement: For one of the tables on the target we needed two additional columns which shall hold the insert and update timestamps for when the row was either inserted or updated. Just to be clear: It was not about getting the timestamps for the inserts or updates…
By Franck Pachot . On the Oracle Database Appliance, like on the Oracle public Cloud, you define the CPU capacity with ‘shapes’. On the latest ODA, the X6, we have a new interface to provision a database. Let’s look at the different shapes available. ODACLI You can provision a new database with the command line ODACLI which replaces the OAKCLI…
