This LNCS conference volume constitutes the proceedings of 28th International Symposium on Database Engineered Applications, IDEAS 2024, in Bayonne, France, in August 2024. The 21 full papers together with 5 short papers included in this volume were carefully reviewed and selected from 34 submissions. The symposium presents papers in the broader field of data management and were organized in seven sessions: (1) Theoretical Issues; (2) Classification; (3) Text and Languages; (4) Big Data; (5) Query Processing and Applications; (6) Machine Learning and Rules; (7) Recommendation, and (8) Indexing and Event Detection.