This book constitutes the proceedings of the 30th European Conference on Advances in Databases and Information Systems, ADBIS 2026, which took place in Orléans, France, during September 28–October 1,2026.

The 22 full papers included in this proceedings book were carefully reviewed and selected from 60 submissions. The book also contains 3 keynote talks and 5 tutorial papers. The contributions have been organized in topical sections as follows: Keynote Talks; core database systems and serialization; similarity, topic modeling and knowledge graphs; data cleaning, semantic discovery and AutoML; Text, GNNs, privacy and Ethereum analytics; integration, auditin, diversification and embeddings; and tutorials.