Holding a transaction open while waiting on a slow external network service keeps a database connection checked out, rapidly exhausting the connection pool. Optimistic vs. Pessimistic Locking
Always declare relationships as FetchType.LAZY . Eager fetching ( FetchType.EAGER ) automatically loads associated entities, causing massive data transfers for fields the application might not even read. High-performance Java Persistence.pdf
In a long-running transaction or a batch job, loading thousands of entities will swell the Persistence Context. The more entities it tracks, the slower the "dirty checking" mechanism becomes, and the more likely you are to run into an OutOfMemoryError . Holding a transaction open while waiting on a
Enter by Vlad Mihalcea. For those who have searched for the High-performance Java Persistence.pdf , you are likely looking for the definitive guide to mastering JPA, Hibernate, and JDBC. This article serves as a comprehensive overview of the book’s core tenets, its real-world application, and why this specific digital resource has become the bible for backend engineers fighting latency. Eager fetching ( FetchType
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