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.
After performing an in-place Oracle linux upgrade I could realize that the oracle service was unusable. I would like to share with you the reason and how to resolve it. Problem description After in-place Oracle linux upgrade from el7 to el8, I could see that the oracle service was not working any more. This service is used to automatically start…
I recently had to upgrade an Oracle Linux production server running 19.30 Oracle databases for one of our customer. In this post, I will share with you the full set of steps that need to be carried out to run an in-place Oracle Linux upgrade when running Oracle databases. The method will be the same to upgrade from Oracle Linux…
Issue I recently had to create a 19c Oracle Database on the Base Database Service on Oracle@Azure. Creating the DB-System failed with the following error: We didn’t see that issue before Database Release Update 19.32. A first test on native Oracle Cloud Infrastructure (OCI) to create a Base DB Service DB-system was successful. However further tests showed that shape “VM.StandardDB.x86”…
How often do I come across this sort of problem when visiting clients? Even more with our customers’ service desk (support) SLAs. We turn up on a Monday morning and there are alerts from the weekend saying [MSSQL] – Instance Dark_Vador-Data(F:): Disk space in GB on server Death_Star is critical Info: NOT OK – Free space: 20 MB out of…
Why does index fragmentation matter less than before ? Logical fragmentation was a problem on spinning disks: an ordered scan on a fragmented index broke the read-ahead into smaller I/Os and each jump cost a disk head movement. On SSD, NVMe and cloud storage, the penalty of non-sequential reads is marginal. And the “physical order” we used to restore so…
For years, we have all scheduled the same thing on our SQL Server environments: a nightly or weekly index maintenance job. We check the fragmentation level, we run a REORGANIZE between 5% and 30%, a REBUILD above 30% and we hope the job finishes before the business day starts. Microsoft recently released a new feature in public preview: automatic index…
In order to be able to test the GenAI Ask EM functionality of OEM 24ai, and after I have first installed an OEM platform from OCI MarketPlace, I have been installing and configuring an Oracle Management agent on one of my DB System that I have in my lab. When the process is still quite the same I still found…
How SQL Server shifts a whole unique column by +1 without ever creating a duplicate using Split/Sort/Collapse.
This summer I start a series of blog posts on the ‘green SQL Server DBA’, as it’s a topic that continues to interest me and one that hasn’t been covered very much so far. I hope you’ll enjoy my tips, starting with this one on unused indexes. When discussing SQL Server performance, we often hear our performance tool say, ‘An…
Recently, I had to renew an SSL certificate on an SQL Server Reporting Services (SSRS) server. The task seemed straightforward: replacing an expired certificate with a new one containing the same configuration. However, once the change had been made, HTTPS wasn’t working anywhere — neither via the usual DNS names nor even when accessing the server directly. Only HTTP remained…
How a forgotten transaction exhausted SQL Server’s worker pool, triggered THREADPOOL waits, and only DAC could fix it.
Introductiom The Zabbix Agent 2 service on a Windows server was repeatedly becoming unresponsive and eventually crashing. The issue caused intermittent monitoring interruptions and required further investigation through Event Viewer messages and Zabbix Agent 2 logs to better understand why the service was no longer responding properly. While monitoring a Windows server with Zabbix Agent 2, we encountered repeated crashes…
