Infrastructure at your Service
There are several methods to find out where time is spent in an execution plan of a query running in an Oracle database. Classical methods like SQL Trace and running a formatter tool like tkprof on the raw trace, or newer methods like SQL Monitor (when the Tuning Pack has been licensed) or running a query with the GATHER_PLAN_STATISTICS-hint (or with statistics_level=all set in the session) and then using DBMS_XPLAN.DISPLAY_CURSOR(format=>’ALLSTATS LAST’). However, what I often…
Introduction Before the freshly come “workload manager” feature on latest Control-M versions, the Control-M users used a lot of workarounds to manage the workload execution. Using Quantitative resources was one of the most used. Request We need to trigger a workflow on demand without having to hold the jobs or release them manually. For example, launch it and stop it at specifics time (on demand). Or preventing side effect if an operation that can impact…
By Franck Pachot . Announced by Larry Ellison last week, here it is: the Autonomous Data Guard. You can try it, unfortunately not on the Free Tier. First you create an Autonomous Database (ATP or ADW) and then you enable Autonomous Data Guard. You know that “Autonomous” is the marketing brand for the services that automate a lot of things, sometimes based on features that are in Oracle Database for a long time. So let’s…
What is Linked server ? Now a days in each company we have different applications and each one of them have different needs in term of databases support. When data exists on multiple databases the management become a little bit hard. For exemple moving some data from an Oracle database to a SQL Server database is not easy. A linked servers is configured to enable the Database Engine to execute a Transact-SQL statement that includes…
By Franck Pachot . J’essaie quelque chose de nouveau. Je publie beaucoup en anglais (blog, articles, présentations) mais cette fois quelque chose de 100% francophone. En sortant du confinement, on reprend les transports (train, voiture,…) et c’est l’occasion de se détendre en musique mais aussi de s’informer avec des podcasts. J’ai l’impression que c’est un format qui a de l’avenir: moins contraignant que regarder une video ou ou lire un article ou une newsletter. Alors…
Over the years I have been working with Documentum, I participated in many migrations and/or upgrades. Just like everything else, this obviously builds up some experience but what if you are pretty new to Documentum and it is your first time working on one? Sure, there is the Documentation from OpenText, which is several dozens of pages (~140, depending on versions) of intense fun so prepare a lot of coffee, you will definitively need some….
By Franck Pachot . The FETCH FIRST … ROWS ONLY syntax arrived in Oracle 12c and is much more convenient than using a subquery with ‘ORDER BY’ wrapped in a “WHERE ROWNUM < …” around it. But as I mentioned in a previous post it required the FIRST_ROWS() hint to get correct estimations. In SQL you don’t want to overload your code for performance, right? The RDBMS optimizer does the job for you. This was…
I came accross an issue by a customer using aws and terraform. He created a server with ebs volume attached to it but he deleted the volume by mistake. He then recreated it manually without using the terraform to do it. Thus, the tfstate wasn’t up to date with the new volume and when executing the terraform plan it wanted to create a new volume withe the same name and everything. So you’ll find the…
log_duration is a useful point for finding slow running queries and to find performance issues also on the applications side using PostgreSQL as database. Another topic is finding issues with Java Applications using Hibernate after a migration to PostgreSQL. Often Hibernate switches from lazy to eager mode and this has massive impact on the application performance. In this context I will also describe one of the most useful extensions: pg_stat_statements. The log duration shown in…
As you probably heard if you weren’t in an underground bunker for the past 2 years, Oracle changed the licensing of the Oracle JDK. If you want to read more about it, there is a good FAQ here. This obviously had some important repercussions everywhere and Documentum wasn’t exempted. I would have a lot to say about the way OpenText tried to adapt since Documentum 16.4 (and kind of failed) but that’s not really the…
My Background Since I started at dbi services sa (before 3 Weeks), I was working and preparing for the SUSE Linux Enterprise 15 certification. I had worked with other Linux distributions like CentOS, Ubuntu and Debian on my old employer. With my basic Linux knowledge I was able to administrate Apache and nginx with virtual hosts, SSL Encryption with Let’s Encrypt, installing and configuring MySQL Database, opening/closing ports for services with firewall-cmd, network configuration and…
By Franck Pachot . I’ll reference Alex DeBrie article “SQL, NoSQL, and Scale: How DynamoDB scales where relational databases don’t“, especially the paragraph about “Why relational databases don’t scale”. But I want to make clear that my post here is not against this article, but against a very common myth that even precedes NoSQL databases. Actually, I’m taking this article as reference because the author, in his website and book, has really good points about…
