Database management

SQL Server AlwaysOn – Failover does not work but everything is green on the cluster

Recently I was called by a customer because the failover on a SQL server AlwaysOn 2 nodes cluster does not work. I connect to the first node of AlwaysOn cluster who is the primary and check the cluster with the(…)

PostgreSQL: Indexes and casting

This is a small reminder to be careful with casting one data type to another in your queries when you want to have an index access rather than a sequential scan. Here is a small example of what can happen:(…)

PostgreSQL 18: Per-relation cumulative statistics for [auto]vacuum and [auto]analyze

This is about another feature which will most likely show up in PostgreSQL 18 later this year. The statistic system is something which gets more and more details with almost every release of PostgreSQL, and PostgreSQL 18 will be no(…)

PostgreSQL 18: Add OLD/NEW support to RETURNING in DML queries

While doing some research on OpenStack (see here for the introduction post), I thought blogging about a new feature for the next version of PostgreSQL might free my head a bit from(…)

dbo vs. db_owner in SQL Server – What are the differences between them?

During the last years working with customers and teaching them in security topics, I realised that a lot of DBAs are not familiar with or aware of the differences between the two “owner” existing in SQL Server. That’s why I(…)

PostgreSQL 18: Change the maximum number of autovacuum workers on the fly

For PostgreSQL it is critical, that autovacuum is able to keep up with the changes to the instance. One of the parameters you can adapt for this is autovacuum_max_workers. This parameter controls how many worker process(…)

FreeBSD basics – 5 – Providing services using Jails

This post builds on top of the previous post in which we’ve created a simple thin Jail. The goal of this post is, to put a bit of automation around this and to provide a simple(…)

PostgreSQL: Maybe we should give ZFS a chance (3) – testing with an aligned record size

In the last post about PostgreSQL on ZFS the pgbench tests showed, that ZFS was slower for the standard tests compared to ext4 on Debian. A comment to that post made me wonder if changing the ZFS record size(…)

PostgreSQL: Maybe we should give ZFS a chance (2) – testing

In the last post we’ve set the baseline for comparing ext4 to zfs when it comes to PostgreSQL. We’ve ended with two PostgreSQL clusters, one running on the ext4 file system while the other is running(…)

New SQL Server Management Studio Version 21 – First Test

Last week, at the Pass Data Summit, they announce the new version of SQL Server Management Studio: SSMS 21 You can find the preview in here. It’s a good opportunity to test this new version before installing it by(…)