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When to gather workload system statistics?

By Franck Pachot . This month we started to give our Oracle Tuning Workshop. And with a new workshop comes new questions. We advise to give to the optimizer the most accurate statsistics that we can have. That(…)

Memory management, OOM issues with SQL Server 2014 In-memory OLTP

Last week I gave a workshop about SQL Server 2014 and the new features. The first day we worked on new In-memory OLTP and different topics such as the new internal storage, the new transaction processing behavior or the(…)

Oracle OPatch and “Archive not applied” error

Recently, I have installed an Oracle 11.2.0.4 RDBMS on a server, and I wanted to install the latest Patch Set Update (PSU) 11.2.0.4.4 from October 2014. During the execution, I fell on the error “Archive not applied” and the job(…)

NLS_LANG on Windows in Europe: WE8MSWIN1252 or WE8PC850?

By Franck Pachot . In europe we have accents and non US7ASCII characters. We need special characterset. I’m not talking about Unicode here that solves all the problems. If you have a Java application, you have no problem: it’s(…)

SQL Server 2014: FCIs, availability groups, and TCP port conflict issues

After giving my session about SQL Server AlwaysOn and availability groups at the last French event “Les journées SQL Server 2014”, I had several questions concerning the port conflict issues, particularly the differences that exist(…)

All you need to know about Oracle Database licensing with VMware

You are running Oracle on VMware and are not 100% sure that you are compliant with the Oracle licensing rules? This article is for you! As I have been confronted several times with Oracle License reviews with VMware installations, I(…)

Flashback logging overhead: ‘db file sequential read’ on UNDO tablespace

By Franck Pachot . in my previous post I’ve reproduced an issue where some bulk insert into a GTT was generating too much undo. But the real case I encountered was worse: the insert was reading lot of(…)

Insert into GTT: bulk with APPEND_VALUES

By Franck Pachot . This post is about the case I had where a GTT was generating too much undo. The effects were amplified by the fact that the database was in flashback logging (see Jonathan Lewis answer in(…)

Don’t forget to configure Power Management settings on Hyper-V

Recently I had the opportunity to audit a SQL Server database hosted on a Hyper-V 2012 cluster. I noticed that the guest operating system had the Power Plan configured to High performance. This is great thing but when I talked to(…)

Managed Backup with SQL Server 2014

In a previous blog post called Backup a SQL Server database from On-Premise to Azure, I presented the different tools to backup your on-premise databases on Azure Storage. SQL Server Managed Backup to Windows Azure was one of(…)