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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(…)

12c online datafile move and ongoing changes

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.

MongoDB Installation

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(…)

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(…)

The dbi services PostgreSQL reference architecture (2) – The community approach

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(…)

The dbi services PostgreSQL reference architecture (1) – The commercial approach

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(…)

SQL Server AlwaysOn : the registry is also important for availability groups

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(…)

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(…)

SQL Server Tips: Find sql logins when “windows authentication only” is enabled

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(…)

SQL Plan Directives strikes again

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(…)