Learning Inheritance and Basic OOP from Real Banking Projects (Back in 2010)

Around 2010, I spent most of my days working as a Java and C developer in the electronic payment industry. At that time, things were very different compared to today. There were no fancy AI coding assistants. No Stack Overflow answers for every problem.And debugging production issues sometimes meant sitting next to a physical EDC […]

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How to Deploy PostgreSQL in Docker for Local Development

When working on modern applications, having a reliable and consistent database environment is crucial for local development. Setting up PostgreSQL directly on your machine can sometimes be cumbersome 😩, especially when dealing with different versions, dependencies, or conflicting configurations. Docker provides a simple and efficient way to run PostgreSQL in an isolated container, ensuring that […]

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Very basic – Reverse a string

Hello There, When i was in a college (around 2000), i had learned an algorithm which i did not know the stuff that i learn here. They told me, it’s a very basic code that i need to achieve at first semester. I was dealing with a coding problem that involved reversing a string. 😩. […]

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3DES algorithm : Double vs Triple Length Keys

Hello There! Just a quick introduction about what is the difference between double length and triple length in 3DES algorithm. I have created some small sample scripts written in Java to generate a 3DES key in different size of length. 1. GENERATING 3DES KEY IN TRIPLE LENGTH OF SIZE 2. GENERATING 3DES KEY IN DOUBLE […]

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Oracle – ORA-00922: missing or invalid option

Hello There! I recently did test in my Java code to have a SQL statement for copy table from TABLE 1 toTABLE 2. I need both tables identical during the application goes boot-up. But, suddenly i got : ORA-00922: missing or invalid option. 1. ORACLE DOCUMENTATION Based on Oracle error documentation ORA-00922 says : Cause […]

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PostgreSQL – Enable field name quote in hibernate

Hello There! Recently, i did a POC that involving 4 databases at the same time in one application. My application just do a simple CRUD in 4 databases which are MySQL, Oracle, Microsoft SQL Server and PostgreSQL. You can image that, one application can be use 4 databases as well. THE PROBLEM At this note […]

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Microsoft SQL Server UDF For REST API call

Hello There! Just continue again what i have done in my previous note. I was writing some UDF for Oracle Database to execute a REST API to CipherTrust Tokenization Server. In this note, i will going to explain how we do REST API at the same way in Microsoft SQL. System administrators, DBAs, and application […]

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