Migrating Spring Boot Apps from PostgreSQL to MongoDB

In this talk, I’ll share my hands-on experience migrating two Spring Boot applications from PostgreSQL to MongoDB. The journey involved redesigning MongoDB collections, refactoring the Java codebase, and efficiently transferring large datasets — including a table with over 25 million records.
Along the way, I encountered and resolved real-world challenges such as memory leaks caused by Hibernate and MongoDB’s “_id is immutable” errors during updates.
The session will include live demos:

• Reproducing and fixing a memory leak
• Performance comparisons showing the impact of MongoDB’s bulk operations