Blog by Rahul Mittal

Introduction Most modern Java applications do not directly use JDBC. Instead, they use an Object Relational Mapping (ORM) framework such as Hibernate through the Java Persistence API (JPA). JPA solves…

Introduction Every Java application eventually talks to a database. Before JPA, Hibernate, and Spring Data existed, Java applications used JDBC directly. Even today, every ORM framework ultimately uses JDBC underneath.…

Introduction Most Java performance problems eventually become SQL problems. Applications become slow because of: Missing indexes Poor joins Full table scans Excessive sorting Improper pagination Incorrect SQL design Large result…

Introduction In enterprise applications, database security is just as important as application security. Many production incidents happen because: Applications use SYS accounts. Developers receive excessive privileges. Passwords never expire. Tables…

Series Overview Modern Java developers are expected to understand much more than writing REST APIs. Enterprise applications require strong knowledge of: Oracle Database SQL tuning JDBC JPA/Hibernate Transactions Performance optimization…

Keys, Dates, Time Zones, UUIDs and Schema Design Introduction Traditional Oracle applications were primarily designed for: Single-region deployments On-premise servers Oracle Forms applications Monolithic systems Modern Java applications are different:…

A Practical Guide for Java Backend Developers One of the biggest mistakes made during schema design is choosing inappropriate data types. A poor datatype decision can impact: Storage requirements Query…

Part 1 – Oracle Database Fundamentals, Schema Design and Best Practices Introduction Most Java developers learn Spring Boot, Hibernate, and REST APIs before fully understanding how databases work internally. However,…

Sets 4–6: Window Functions, Query Optimization, Transactions and Real Interview Problems This article continues the Backend Developer SQL series and focuses on the topics typically asked in 3–10 years experienced…

30 SQL, RDBMS and Database Questions from Beginner to Advanced Level Database knowledge is one of the most important skills for backend developers. Whether you work with Oracle, MySQL, PostgreSQL,…