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Support and see how the magic of this self hosted blog happens

By | August 23, 2021

There were so many times when I had to search for hours for a solution that looked trivial in the end when I found it explained by some stranger on a blog or forum. There are cases when after reading manuals, documents and forums there is still no clear solution and then I wish someone… Read More »

#Oracle # SQL Covert view to table issue: ORA-01723: zero-length columns are not allowed

By | July 31, 2023

In an Oracle database I was trying to convert an existing view to a table and preserve the data in it. For most of my views the following SQL worked perfectly: Then in one on the instances the following error occurred: While inspecting the SQL code of the views I noticed that the view with… Read More »

My #vintage #turntable set-up.

By | June 21, 2023

Several months ago I moved my childhood turntable setup to my new place. I will just post here some images of the set-up I like so much. Basically it was the standard turntable you could buy in the late 1980s in communist Romania. I remember that my dad bought it sometimes in 1983 or 1984.… Read More »

#Jboss: Data source connection optimizations

By | June 21, 2023

In a high load system deployed on Jboss Application Server the following optimizations for data source pool resources may be needed. 1. Change the minimum and maximum pool size of a data source (MyDS). This will ensure that we always have a minimum number of allocated connections and also we set a threshold to the… Read More »

Activate #infinispan second level cache with #jboss and #hibernate

By | November 23, 2022

Second level cache is an extremely powerful way to improve performance of an enterprise application if done right. In the following I will explain how to activate and configure second level cache when using Hibernate and Jboss 7.4+ application server. Jboss 7.4 comes with Infinispan as the build in second level cache solution. This makes… Read More »

#Oracle quick way to investigate slow or time consuming application queries

By | November 21, 2022

In the following post I will describe my quick procedure I always use to debug the database queries generated by an application that hit an Oracle database. In a lot of cases your queries that hit the database are not written explicitly by a developer. That may be the case when intermediate layers as Hibernate… Read More »

#windows #powershell how to kill zombie Edge session

By | October 31, 2022

Often times I find trying to start Edge on an old data-center jump station and I just click and nothing happens. This is the direct result of an Edge process that went zombie. A quick way to kill an Edge session that is acting as a zombie and will not allow you to start a… Read More »

#SQL #Oracle : Move all indexes to a different tablespace

By | October 18, 2022

In general is good to have a separate tablespace for your index tables. Sometimes the default tablespace, in our case DATA, is used by an application using hibernate layer to automatically create all the tables and indexes. Then the issue is how to move the automatically created indexes to the special created tablespace for indexes,… Read More »

#Linux #Fedora #Java defaults and jasper reports compile issues

By | September 28, 2022

A common mistake is to set the alternatives just for java sdk. This can lead to issues when several java versions are present. Jasper Reports a well knows Java library used to generate ad-hoc pdf reports compiles the report templates and the temporary classes using the default system javac not the javac of the java… Read More »

#SpringBoot : Create a conditional Spring Boot Bean only if asked by an external configuration, not using @Conditional #Java

By | September 7, 2022

Usually Spring Boot beans are created automatically before the application start and autowired as needed. What if we need to create a Spring bean only if some configuration file requires it. This way of writing code is very useful when trying to write highly configurable enterprise applications where you want to be able what components… Read More »