Development & Performance

Sudden drop of the page life expectandy but don’t panic yet!

A couple of weeks ago, I had an interesting discussion with one of my customer about the page life expectancy (aka PLE). He asked me if monitoring the metric value is a best practice because he often noticed a big(…)

Changing an existing partition configuration … Well, not so easy!

This time let’s talk about an interesting customer scenario where table partitioning was implemented on a table with 100 GB of data on SQL Server 2014. Partitioning in this context aimed to save disk space  (archive data were compressed) , help(…)

NOLOCK is definitely not what you may expect …

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(…)

Dynamic filters and “kitchen sink” queries dilemma

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(…)

Enable 10046 Tracing for a specific SQL

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(…)

Availability groups : readable secondary replicas and impact on the storage layer

Do read-only capabilities of an availability group have a performance impact for databases? The quick response is yes but let’s see why in this blog post. First of all, when we want to use our secondary replicas as read-only, we(…)

SQL Server Extended Event: Eine Deadlock-Event aus der “system_health” Überwachung

Wie Sie vielleicht wissen, gibt es eine Überwachung über Extended Events: system_health. Kürzlich fragt mich ein Kunde an, um ein zufälliges Deadlock-Problem zu analysieren...

SQL Plan Directive: disabling usage and column groups

By Franck Pachot . Yesterday I came upon a comment on oracle-l while I was reading my slides for the UKOUG TECH15 SuperSunday. I've one slide and one demo about disabling SPD usage but that's not(…)

Trying AppDynamix – monitoring application from user to database

By Franck Pachot . I like to come upon new monitoring software that help to go quickly from user response time to root cause. And I love applications that can be installed easily and at which I can give a(…)

Software architecture vs code representation

Tuesday the 10th of November I attended a public lecture at Swiss Java User Group in Zürich. Topic of the pretension was to describe and address challenges any project manager can encounter, when reflexion switches from perspective of software(…)