JDBC Profiling with VisualVM
Introduction In this article, we are going to see how we can do JDBC profiling using the VisualVM tool to find slow-running SQL queries or discover N+1 query issues.
MySQL rewriteBatchedStatements configuration property
Introduction In this article, we are going to see how MySQL rewriteBatchedStatements works when using JDBC, JPA, or Hibernate. I first researched this MySQL configuration property when I was writing the batching chapter of my High-Performance Java Persistence book, and, back then, I discovered that this setting allows batching plain Statement by rewriting the SQL string that is sent to the database. However, the MySQL 6 Connector/J documentation mentioned that: for prepared statements, server-side prepared statements can not currently take advantage of this rewrite option So, for a long time, I wrongly… Read More
The JPA and Hibernate second-level cache
Introduction In this article, I’m going to explain how the JPA and Hibernate second-level cache mechanism works and why they are very important when it comes to improving the performance of your data access layer.
SQL Server JDBC – Set sendStringParametersAsUnicode to false
Introduction In this article, I’m going to explain why you should always disable the sendStringParametersAsUnicode default JDBC Driver setting when using SQL Server.
MySQL JDBC Statement Caching
Introduction In this article, we are going to see how we can enable the MySQL JDBC Driver Statement Caching mechanism, which, unfortunately, is not enabled by default. No matter what data access framework you are using, you still need to configure the JDBC Driver if you want to get the most out of the MySQL database engine.
The JPA and Hibernate first-level cache
Introduction In this article, I’m going to explain how the JPA and Hibernate first-level mechanism works and how it can improve the performance of your data access layer. In JPA terminology, the first-level cache is called Persistence Context, and it’s represented by the EntityManager interface. In Hibernate, the first-level cache is represented by the Session interface, which extends the JPA EntityManager one.
Why and when you should use JPA
Introduction If you are wondering why and when you should use JPA or Hibernate, then this article is going to provide you an answer to this very common question. Because I’ve seen this question asked very often on the /r/java Reddit channel, I decided that it’s worth writing an in-depth answer about the strengths and weaknesses of JPA and Hibernate. Although JPA has been a standard since it was first released in 2006, it’s not the only way you can implement a data access layer using Java. We are going to discuss… Read More
JDBC Driver Maven dependency list
Introduction Ever wanted to connect to a relational database using Java and didn’t know which JDBC Driver Maven dependency to use? If so, this article is surely going to help you from now on.
The best way to call a stored procedure with JPA and Hibernate
Introduction In this article, you are going to learn the best way to call a stored procedure when using JPA and Hibernate so that the underlying JDBC resources are released as soon as possible. I decided to write this article since the way Hibernate handles stored procedures can lead to ORA-01000: maximum open cursors exceeded issues on Oracle as explained in this Hibernate forum thread or StackOverflow question.
PostgreSQL reWriteBatchedInserts configuration property
Introduction The PostgreSQL JDBC Driver has been adding a lot of very useful optimizations, and one of the lesser-known ones is the reWriteBatchedInserts configuration property. In this article, you will see how the reWriteBatchedInserts JDBC configuration property works in PostgreSQL, and how it allows you to rewrite INSERT statements into a multi-VALUE INSERT.
