The two-volume set, LNCS 14146 and 14147 constitutes the thoroughly refereed proceedings of the 34th International Conference on Database and Expert Systems Applications, DEXA 2023, held in Penang, Malaysia, in August 2023.

The 49 full papers presented together with 35 short papers were carefully reviewed and selected from a total of 155 submissions. The papers are organized in topical sections as follows:
Part I: Data modeling, database design, query optimization, knowledge representation,
Part II: Rule-based systems, natural language processing, deep learning, neural networks.