التحميل الكسول واستثناؤه

في هذا الدرس

explain lazy versus eager and LazyInitializationException.

الموضوعات المخطط لها

• Lazy: the relation is loaded on first access, using a proxy placeholder.
• Eager: loaded immediately with the parent, always, even when unused.
• LazyInitializationException: you touched a lazy relation after the persistence context closed.
• Do not "fix" it by making everything EAGER; that creates huge hidden queries.
• Load what you need inside the service transaction, or use a projection/DTO.