Spring Boot Hibernate Batch Fetching

In this tutorial, you'll learn about Fix Spring Boot Hibernate Batch Fetching Not Batching. We cover key concepts, practical examples, and best practices.

The Problem

Lazy collections load each element individually despite @BatchSize annotation.

Quick Fix

Apply @BatchSize on entity

Wrong:

@Entity
public class Order { } // No @BatchSize

Output:

N+1 queries

Right:

@Entity
@BatchSize(size = 25)
public class Order { }

Output:

Orders loaded in batches of 25

Set global batch size

Wrong:

# No global setting
spring.jpa.properties.hibernate.default_batch_fetch_size=0

Output:

Default batch size 1

Right:

spring.jpa.properties.hibernate.default_batch_fetch_size=16

Output:

Global batch size set

Use batch fetch mode

Wrong:

// Default fetch mode

Output:

Suboptimal loading

Right:

spring.jpa.properties.hibernate.batch_fetch_style=PADDED
// PADDED, DYNAMIC, or LEGACY

Output:

Optimal batch fetching

Prevention

• Add @BatchSize on entity classes
• Set global hibernate.default_batch_fetch_size
• Use PADDED batch fetch style for optimal results

Common Mistakes with boot hibernate batch fetching

1. Misunderstanding that String is [Char] with poor performance for large text operations
2. Using foldl instead of foldl' causing stack overflow on large lists
3. Forgetting deriving (Show, Eq) on custom data types needed for debugging

These mistakes appear frequently in real-world SPRING code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

FAQ

This quick fix is part of the DodaTech Spring & JVM ecosystem series. Built by the developers of Doda Browser, DodaZIP, and Durga Antivirus Pro.