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.
Let’s talk about a funny story that concerns an interesting issue that I faced a couple of months ago at one of my customers. Initially, the problem concerned only the creation of an availability group listener but after deleting the related availability group, he noticed quickly that the deletion failed but even more strange, he noticed that the virtual network…
Today I will talk about the new parameter file checks available to continue the series of blog posts about the new features of GoldenGate 12.2. There are three themes that I will present you: Checkprm utility Info param Getparaminfo Checkprm utility This utility can be used to validate a parameter file (.prm). It is located in the home of the…
For those who still believe that using nolock hint is a lock-free process, keep reading this blog post. I wrote a previous blog post 3 years ago, when I was at one of my customer and we had an interesting discussion about the nolock hint with reporting queries. I convinced him that nolock continues to generate locks even if the…
By Franck Pachot . Here is a long answer for a question on our forum about online move: what is internal mechanism to store/keep ongoing changes in that particular datafile while copying is in progress. The short answer is that there is absolutely no lock, just small synchronization and messaging between sessions. And a very small overhead while the move…
In this blog posting we will see how to install MongoDB on a Linux distribution. MongoDB is supported for Linux, Mac, Windows and Solaris. Linux distribution First, determine your Linux distribution in order to download the appropriate MongoDB binaries. cat /proc/version MongoDB is supported on the following operating systems: Platform 3.2 3.0 2.6 Amazon Linux × × × Debian 7…
Dealing with dynamic filters is a common scenario with management software or ERP. Indeed, users should like to have the flexibility to filter and sort their business data as they want in order to be efficient. Target and operate quickly on the right data is in line with the required performance every day. This is at least what I could…
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…
When it comes to designing a PostgreSQL architecture that fits your requirements there are a couple of things to think about: Do you need a HA setup? How shall backups and restores being done and how shall all of these components get monitored? Do you need vendor support for all the tools that make up the architecture? At dbi we…
A couple of months ago, we experienced with my colleague Nathan Courtine a weird issue at one of our customers. This issue concerned an AlwaysOn availability group and more precisely to the WSFC cluster layout. I can’t say strongly enough that the AlwaysOn availability group runs on the top of the WSFC and having a good understanding of the internal…
Available methods to enable 10046 trace are described in My Oracle Support Note 376442.1. You can enable 10046-tracing – on session level (alter session) – for other sessions (e.g. with oradebug, the package DBMS_MONITOR or DBMS_SYSTEM) What is not covered with the methods above is the possibility to trace a specific SQL-statement, which runs “somewhen” in the future on the…
A customer asks me to find all sql logins enabled on servers where windows authentication only is enabled. The goal is to clean sql logins on all servers through the CMS (central management server). In some cases, sql logins are created even if the authentication is set to “Windows authentication only mode”. I think that this query is interesting and…
By Franck Pachot . 12c SQL Plan Directives, a side effect, a bad application design, a bug… and the occasion to show how to quickly troubleshoot. An application has long response time since 12c migration. No blind guesses, no reason to compare with previous version, let’s just troubleshoot performance with methodical approach. Time Model You should already know that, I…
