Introduction

Welcome to a new issue of the High-Performance Java Persistence Newsletter in which we share articles, videos, workshops, and StackOverflow answers that are very relevant to any developer who interacts with a database system using Java.

Articles

The pick of this edition is this article, which explains how you can use the Hibernate Statistics in order to assert the SQL queries executed by Hibernate. The Hibernate Statistics provides a lot of information that you can use to determine whether caching is effective or to validate the performance gains of a given optimization.

When using a relational database system, it’s very common to use auto-incremented numeric Primary Keys. To avoid guessing other identifier values, you can use various solutions. Most often, developers use UUIDs, but this doesn’t always play out well as UUIDs are quite large, and the version 4 identifiers start with random bytes, therefore compromising B+Tree indexes. If you want to see an efficient method to hide record identifiers, check out this article.

A very good article I read was this one about the cost of fragmentation in MySQL. The issue of random INSERTs applies to other databases that use clustered Indexes, like SQL Server or Index-Organized Tables in Oracle.

If you’re using SQL Server, then you should know that you can optimize batched INSERT into BULK INSERT by activating the useBulkCopyForBatchInsert JDBC configuration. If you’re interested in this topic, check out this article.

Another interesting article I read is this one, which described the Multi-Regional Architecture employed by Monday.com.

When using JPA bidirectional associations, it’s important to have synchronization methods. However, using these methods properly is not always obvious, and for this reason, I explained some best practices in this article.

Another very good read was this article about various features we’d really benefit from if the DB provided to us, like soft deletes, multi-tenancy, or data versioning.

If you’re using PostgreSQL and want to speed up your data access layer, you should make sure that your SQL queries can benefit from the existing statement caching feature. For more details about this topic, check out this article.

Best Tweets

Here are the best tweets I posted since the last newsletter:

Just because you are a back-end developer, it doesn't mean you cannot come up with a beautiful UI design. pic.twitter.com/Pf2m5o9Obj

— Vlad Mihalcea (@vlad_mihalcea) August 16, 2023

Another day has passed without having to invert a binary tree or implement a sorting algorithm.

— Vlad Mihalcea (@vlad_mihalcea) August 29, 2023

Don't avoid framework or database-specific features in the name of portability.

For instance, how many times did you have to switch the JPA provider?

Or, how many times did you have to switch database systems in an enterprise project?

Instead of preparing for a future that…

— Vlad Mihalcea (@vlad_mihalcea) August 5, 2023

Developing software is easy.

Developing software with other people is hard.

— Vlad Mihalcea (@vlad_mihalcea) August 12, 2023

Developers are very indulgent when it comes to their own code but extremely critical when it comes to code writen by others

— Vlad Mihalcea (@vlad_mihalcea) August 14, 2023

Project Releases

PostgreSQL 15.4 was released, and it provides many fixes. If you’re using PostgreSQL 15, you might want to consider an upgrade.

Hypersistence Utils 3.5.2 was released, and it brings you a fix to the ListArrayType.

Get in touch with my latest articles!

SUBSCRIBE

StackOverflow Answers

The following StackOverflow answers have been trending since the last newsletter episode:

• Hibernate EmptyInterceptor onFlushDirty() is not executing
• Hibernate insert fails when embedded key contains an IDENTITY column on SQL Server
• How to set a default entity property value with Hibernate
• Atomic locking of all rows of a JDBC batch update
• High memory usage when using Hibernate