隨著資料量日益增長、業務邏輯的複雜化以及微服務架構的興起，傳統的 CRUD 亦即創建 (Create)、讀取 (Read)、更新 (Update) 和刪除 (Delete)等資料庫 操作和 ORM 模式在規模性、資料一致性以及歷史追蹤上面臨挑戰。因此，Event Sourcing (ES)被提出作為一種可能的解決方案，ES 不是只儲存最終狀態， 而是記錄導致該結果的所有變更，除了提供系統狀態變更的完整歷程追蹤和審 計，也提升了系統在面對大規模資料操作時的擴展性，還確保了在分散式系統 中的資料一致性。雖然理論上 ES 的追溯性和審計性得到了認可，但在實作層 面上，對於採用 ES 的系統架構對效能影響的研究仍然有限。本研究探討了 ES 架構在現代軟體系統中的應用，特別是對於系統效能、規模性的影響。為此， 本研究以 JPetStore 電子商務網站作為研究案例，評估了不同的架構設計，包括 傳統上使用 CRUD 的架構和整合 ES 的變體。透過這些實作，本研究旨在提供 實證基礎以輔助系統設計和技術選擇考量的討論。此外，本研究也關心 ES 實 作過程中的挑戰，ES 的實作需要開發者對業務流程有深入理解，並且能夠處理 事件引起的各種狀態變更。本論文透過深入分析和比較不同架構，揭示採用 ES 對軟體系統效能的具體影響，並分享從傳統 CRUD 重構為 ES 架構的實作心得。

With the increasing volume of data, the complexity of business logic, and the rise of microservices architecture, the traditional CRUD model—Create, Read, Update, Delete—and ORM patterns face challenges in scalability and data consistency. Consequently, Event Sourcing (ES) has been proposed as a potential solution. Unlike traditional methods that only store the final state, ES records all changes leading to that result. This not only provides a complete history and audit trail of system state changes but also enhances system scalability in handling large-scale data operations and ensures data consistency in distributed systems. Although the traceability and auditability of ES are theoretically acknowledged, there is still limited research on the performance impact of systems adopting ES at the implementation level. This study explores the application of the ES architecture in modern software systems, particularly its impact on system performance and scalability. To this end, the research uses the JPetStore e-commerce website as a case study, implementing different architectural designs, including the traditional CRUD-based architecture and its variants integrating ES. Through these implementations, this study aims to provide empirical evidence to support discussions on system design and technical considerations. Additionally, the study addresses challenges in implementing ES, such as technical complexity and event design. Implementing ES requires developers to have a deep understanding of business processes and to manage various state changes triggered by events. This thesis, through in-depth analysis and comparison of different architectures, reveals the specific impacts of adopting ES on software system performance and shares insights from the process of refactoring from traditional CRUD to ES architecture.

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