19. 06. 2022.

How to speedup pooling queries from the Oracle database

This post is a kind of extension of my previous post named “How to index only rows of interest” which can be found on the following link: https://www.josip-pojatina.com/en/how-to-index-only-rows-of-interest/   Having issues with pooling queries are very common in old, SOA based architectural style, where ESB (Enterprise Service Bus) are throwing the same query again and […]

30. 05. 2022.

How to get 100% cache hit rate by using Change Data Capture & Redis

In this blog I’ll explain how to get 100% cache hit rate by using CDC (Change Data Capture) technology and Redis cache.   There are multiple benefits of having caching layer in front of back-end database system. By fetching data from the cache instead of back-end we are actually free up valuable database resources for […]

04. 02. 2022.

StreamSets review – creating real time data pipelines in no time

In this post I’ll try to review StreamSets Data Collector, one of the most popular tools for creating smart data pipelines for streaming, batch and change data capture, which allows you to move data around in a near real time.   First I’d like to point out that the whole review is my own personal […]

29. 11. 2021.

Complex near real-time transformations in data pipelines

For many years, ETL daily batch job was the dominant way to perform data transformations before loading in Data Warehouse. These days requirements are quite different starting with the most important one which is to ensure that new data has to be available for AI/ML and analysis near real time. Moreover, classical DWH databases are […]

05. 02. 2019.

OpenJDK Mission Control – how to install it properly

If there is one tool that have almost all what is needed for monitoring, troubleshooting and tuning Java apps, that will be OpenJDK Mission Control.   There are several reasons why JMC will be hot topic in Java events from now on: More than 95% of all issues related to JVM, application servers, deployed apps […]

24. 08. 2018.

Performance tuning by using optimistic instead of pessimistic locking

Even though Oracle Db started with optimistic locking many years back, old fashion programming style can still be observed too often. In this article I’ll explain why you should avoid using pessimistic locking as mach as possible, and will show one of the alternative way to do the same task by using optimistic locking. I’ll […]

28. 07. 2018.

Supplemental logging – when to use it (and when not)

Supplemental logging feature along with streaming and CDC (change data capture) is available for a long time and is used mainly as one of the integration options especially for loading data from transactional (OLTP) into DW (Data Warehouse) staging tables. During my engagement on project for one large retailer, I noticed significant performance penalties due […]

09. 10. 2017.

How to call Web Service from the Oracle database

In this article I want to explain what you need to do to be able to call Web Service. Although there are many good articles on the web, no one provide complete step by step instructions on how to do it. My goal in this article is to explain the complete procedure in a simple […]