Java app performance improved by JVM config tuning

Java Performance Tip 🚀 Dealing with large datasets in Spring Data JPA? Stop loading everything into memory! Use Stream-based queries with proper fetch size configuration for better memory management and performance. ✅ Old way: Loads entire result set into memory - potential OutOfMemoryError ✅ New way: Streams data in batches - efficient memory usage and better performance Key Benefits: 🎯 Prevents OutOfMemoryError with large datasets ⚡ Processes data in chunks (batch of 1000 records) 💾 Lower memory footprint 🔄 Works seamlessly with Java Streams API 📊 Perfect for data processing and reporting Pro Tips: Always close streams properly (use try-with-resources) Use @Transactional(readOnly = true) on service methods #Java #SpringBoot #SpringData #JPA #Hibernate #Performance #BestPractices #CleanCode #SoftwareDevelopment #BackendDevelopment #TechTips

When converting between Java objects — such as entities, DTOs, or database objects — developers often rely on Jackson’s ObjectMapper for its convenience and flexibility. However, subtle differences in https://lnkd.in/dTgK9kKH

Master Quarkus’s New SQL Import Trick — ZIP Your Database Like a Pro Quarkus 3.17+ introduces a powerful new capability: importing SQL scripts directly from ZIP files. It’s a small feature with big impact for Java developers working with Hibernate ORM + Panache. In this hands-on tutorial, I wrapped it in a fun “Zombie Survival Registry” demo to make learning memorable. ✅ Simplify your database setup ✅ Bundle scripts for CI/CD ✅ Learn the new ZIP import support 👉 Read the full article: https://lnkd.in/dKZZfGM8 #Java #Quarkus #Hibernate #PostgreSQL #SoftwareDevelopment #DeveloperExperience

JPQL (Java Persistence Query Language) is your best friend when you want more control over data fetching. - Instead of returning entire entities, you can map results directly into a DTO — saving memory and speeding things up. Small tweaks like this make your app cleaner and more efficient! 🚀 #JPA #SpringBoot #Hibernate

How to Create a Composite Primary Key in JPA Sometimes a single column isn’t enough to uniquely identify a record - that’s when we use a composite primary key. JPA gives two clean ways to implement it: @IdClass and @EmbeddedId. > The @Embeddable class holds the combined key fields. > The entity uses @EmbeddedId to mark the composite key. When to use: When two or more fields together uniquely identify a row When modeling many-to-many join tables When avoiding auto-generated IDs Composite keys keep your data consistent and enforce real-world uniqueness directly in the database. #SpringBoot #JPA #Hibernate #Java

💡 Day 3 of my 𝗝𝗮𝘃𝗮 𝗕𝗮𝗰𝗸𝗲𝗻𝗱 𝗤𝘂𝗲𝘀𝘁𝗶𝗼𝗻 𝗼𝗳 𝘁𝗵𝗲 𝗗𝗮𝘆 𝘀𝗲𝗿𝗶𝗲𝘀: 🧠 Question: You’re working on a Spring Boot application that interacts with a relational database. You notice that for every request, multiple queries are executed for fetching related entities - causing performance issues. 👉 What is the N+1 query problem in JPA/Hibernate, and how can you avoid it? ✅ Answer: The N+1 query problem happens when Hibernate fires: 1 query to fetch parent records N queries to fetch child records for each parent This results in N+1 queries, hurting performance. To avoid it: > Use fetch join 𝘚𝘌𝘓𝘌𝘊𝘛 𝘶 𝘍𝘙𝘖𝘔 𝘜𝘴𝘦𝘳 𝘶 𝘑𝘖𝘐𝘕 𝘍𝘌𝘛𝘊𝘏 𝘶.𝘰𝘳𝘥𝘦𝘳𝘴 > Use @EntityGraph to pre-fetch relationships > Enable batch fetching 𝘩𝘪𝘣𝘦𝘳𝘯𝘢𝘵𝘦.𝘥𝘦𝘧𝘢𝘶𝘭𝘵_𝘣𝘢𝘵𝘤𝘩_𝘧𝘦𝘵𝘤𝘩_𝘴𝘪𝘻𝘦=20 > Always monitor SQL logs to detect hidden N+1 issues. ✅ Fetch joins, entity graphs, and batch fetching = faster DB access & fewer queries ⚡ See you tomorrow for Day 4 👋 #Java #SpringBoot #Hibernate #JPA #Performance #BackendDeveloper #ContinuousLearning #QuestionOfTheDay

Given millions of data records and ability to search efficiently (with duplicates allowed) — which data structure would you pick and why (In java)? https://lnkd.in/eeDEySj3

Day 1 of Advanced Java – JDBC (24 Oct 2025) Today I started learning **Advanced Java**, beginning with **JDBC (Java Database Connectivity)**. ✨ JDBC** is an API that helps Java applications connect and interact with databases. Before JDBC, data was stored in files — which led to issues like lack of security, redundancy, and complex data handling. Types of JDBC Drivers: ✨Type 1 – JDBC-ODBC Bridge, ✨Type 2 – Native API, ✨ Type 3 – Network Protocol (Middleware), ✨ Type 4 – Thin (Pure Java & Most Used). *Basic Steps to Connect Java with Database* * Load Driver, * Establish Connection, * Create Statement, * Execute Queries, * Close Connection.. 🐒 Key takeaway: JDBC provides a secure and efficient way to connect Java programs with databases — a core concept for backend and full-stack developers. 👉 Guided By: Levaku Lavanya Mam, Uppugundla Sairam Sir, Saketh Kallepu Sir. #Java #AdvancedJava #JDBC #LearningJourney #FullStackDevelopment #Programming #SoftwareEngineering 🙌 JDBC Architecture:

JDBC vs Spring JDBC — Understanding the Difference As part of my Spring Boot learning journey, I explored how Spring JDBC simplifies traditional JDBC — and the difference is huge! 🚀 When using plain JDBC, we manually handle everything — 👉 establishing connections 👉 creating statements 👉 handling exceptions 👉 closing ResultSets But Spring JDBC (via JdbcTemplate) takes care of all this automatically, so we can focus purely on writing SQL logic. Feature JDBC Spring JDBC Connection handling Manual Automatic Boilerplate code High Very low Exception handling Checked SQLException Translated to runtime DataAccessException Transaction management Manual Supported by Spring Integration Standalone Integrated with Spring Boot ecosystem 👉 Key takeaway: Spring JDBC saves time, reduces code, and makes database access cleaner and more maintainable — especially in enterprise-level applications. I’ll be diving deeper into Spring Data JPA next to see how it abstracts SQL even further! 💻✨ #SpringBoot #JavaDeveloper #JdbcTemplate #SpringJDBC #BackendDevelopment #LearningJourney #Java

Difference Between flush() and commit() in JPA Understanding how JPA writes data to the database is crucial for debugging and performance tuning. Two terms often confused are flush and commit - but they work very differently. 1. What is flush()? flush() pushes the changes from the persistence context (Hibernate’s in-memory cache) to the database temporarily. > SQL statements are executed > But the transaction is not completed > Data is still rollback-able 2. What is commit()? commit() ends the transaction and makes all changes permanent. > Executes a flush internally > Finalizes and saves data > Cannot be rolled back after commit Key Difference: Flush = sync with DB (temporary) Commit = finalize transaction (permanent) #SpringBoot #JPA #Hibernate #Java