Tag: 학습
All the articles with the tag "학습".
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Spring Boot #5 — Servlets, Embedded Tomcat, Thread Pools, and the WAS Layer
Every time I fired off a curl request, a new thread got added. Here's a breakdown of how Tomcat pre-hires workers and assigns requests to them, the balance between thread pools and DB connection pools, and the confusing dual identity of 'Apache'.
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Spring Boot #4 — Transactions, Relationships, N+1, and Fetch Join
I connected entities with @ManyToOne and ran a full query, and instead of 1 query, 6 came out. I fixed the N+1 problem caused by LAZY loading with fetch join, and worked through the atomicity and dirty checking of @Transactional.
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Spring Boot #3 — Connecting PostgreSQL with JPA · CRUD with Entities and Repositories
I replaced the in-memory List CRUD with an actual PostgreSQL setup. From build.gradle dependencies to application.properties, from record to @Entity, why JpaRepository is an empty interface but CRUD still works, and the dividend of layer separation where I didn't change a single line in the controller.
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PostgreSQL Basics — CRUD and the Korean Sorting (COLLATE) Trap
I'd only used SQLite before, so this was my first time touching PostgreSQL. From CREATE to mapping CRUD, and the collation problem where ORDER BY wouldn't sort Korean text alphabetically.