Database Administration & Monitoring What is more efficient: arrays or single column values? 15.06.2015 by Daniel Westermann In PostgreSQL ( as well as in other rdbms ) you can define columns as arrays. What I wondered is: What is more efficient when it comes to space: Creating several columns or just creating once column as array? The(…)
Database Administration & Monitoring SQL Interpolation with psql 15.06.2015 by Daniel Westermann The PostgreSQL psql utility provides some really nice features. One of these features is SQL interpolation which allows us to do interesting things, e.g. reading files and analyze the results directly in the database. This post(…)
Database Administration & Monitoring A free PostgreSQL cloud database? 14.06.2015 by Daniel Westermann Recently I was looking for a free PostgreSQL cloud database service for testing. Why? Because I’d like to use such a cloud instance for testing no matter on which workstation or OS I am currently on. Another reason is, that(…)
Database Administration & Monitoring PostgreSQL portable? 12.06.2015 by Daniel Westermann What a surprise: Headed over to the sourceforge page, downloaded, installed (which is just a matter of next/next/next) : Not really the latest patchset but far more than I(…)
Database Administration & Monitoring Get the main information from Windows Server with PowerShell 18.05.2015 by Nathan Courtine This blog will present you a way to retrieve Windows Server main information via PowerShell. The goal is to be able to automate the extraction of information for different purposes: audit, report generation, dashboards… Disclaimer: I am not a(…)
Database Administration & Monitoring, Oracle Flashback logging overhead: ‘db file sequential read’ on UNDO tablespace 09.01.2015 by Oracle Team 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(…)
Database Administration & Monitoring, Oracle Oracle: an unexpected lock behavior with rollback 26.10.2014 by Oracle Team By Franck Pachot . Here is an odd Oracle behavior I observed when a transaction that acquired a lock is rolled back. Note that this is related to a specific combination of locks that should not be encountered in(…)
Database Administration & Monitoring, Oracle Oracle 12.1.0.2: Wait event histograms in μs 04.08.2014 by Oracle Team By Franck Pachot . When an Oracle Database spends a high percentage of its DB time in User I/O, I usually check the wait event histograms in order to see if the storage system is working well. But today,(…)
Database Administration & Monitoring, Oracle Linux: how to monitor the nproc limit 10.06.2014 by Oracle Team By Franck Pachot . You probably know about ‘nproc’ limits in Linux which are set in /etc/limits.conf and checked with ‘ulimit -u’. But do you know how to handle the monitoring and be alerted when you’re close the fixed(…)
Database Administration & Monitoring, Oracle Oracle Exadata – poor optimization for FIRST_ROWS 28.05.2014 by Oracle Team By Franck Pachot . In a previous blog, I discussed the difference between rownum and row_number(), in particular their behaviour in implicitely adding a first_rows(n) to the optimizer. That reminded me that I forgot to blog about an(…)