java-jpa-hibernate-performance

name	java-jpa-hibernate-performance
description	Use this skill when statically reviewing JPA/Hibernate data access for fetch-strategy correctness and reliability — N+1 exposure, JOIN FETCH vs @EntityGraph vs @BatchSize vs DTO projection, LazyInitializationException and open-in-view misuse, pagination combined with a collection fetch (cartesian product), MultipleBagFetchException, and HikariCP connection-pool sizing. Trigger when a user provides entity classes, mappings, Spring Data repositories, or JPQL/Criteria queries and asks why queries are slow, why a page loads too much, or whether their data access is correct. Reads source and mapping only; it never opens a database connection, runs a query, or executes migrations.
allowed-tools	Read Grep Glob
metadata	{"author":"github: Raishin","version":"0.1.0","updated":"2026-07-17","category":"database","lifecycle":"experimental"}

Java JPA/Hibernate Performance Review

Purpose

This skill statically reviews JPA/Hibernate data access for fetch-strategy correctness, query shape, and connection reliability. Data access is only sound if associations are fetched by explicit, access-shaped strategies rather than lazy-by-accident or eager-by-default, if pagination does not silently load a cartesian product into memory, if the request is not leaning on open-in-view to resolve lazy state in the view layer, and if the connection pool is sized from measured hold time rather than a round number. The review catches N+1 patterns, eager collections, pagination-with-fetch, MultipleBagFetchException risk, open-in-view misuse, and mis-sized HikariCP pools.