Developed a comprehensive database management application that simulates the entire lifecycle of credit card payment transactions within the Visa network. The system models complex interactions between cardholders, issuing banks, acquiring banks, and merchants through a relational database architecture. Key Features: Implemented a fully normalized SQL database schema with 11 interconnected tables tracking everything from transaction authorization to settlement Built a Java GUI application with dedicated panels for custom queries, CRUD operations, complex joins, views, and aggregation functions Designed transaction processing workflows capturing real-world payment network operations including authorization, fraud detection, and settlement Modeled financial data relationships including interchange fee structures, merchant category codes, and multi-currency support Applied database security best practices including tokenization of sensitive card data Technologies Used: Java, MySQL, JDBC, Swing UI, Maven This project demonstrates strong understanding of financial transaction systems, database design principles, and enterprise application architecture.