Learning database optimization techniques: the state-of-the-art and prospects

Download PDF
Open Webpage

Shaojie Qiao, Han-Lin Fan, Nan Han, Lan Du, Yu-Han Peng, Rong-Min Tang, Xiao Qin

Published: 2025, Last Modified: 23 Jan 2026Frontiers Comput. Sci. 2025EveryoneRevisionsBibTeXCC BY-SA 4.0
Abstract: Artificial intelligence-enabled database technology, known as AI4DB (Artificial Intelligence for Databases), is an active research area attracting significant attention and innovation. This survey first introduces the background of learning-based database techniques. It then reviews advanced query optimization methods for learning databases, focusing on four popular directions: cardinality/cost estimation, learning-based join order selection, learning-based end-to-end optimizers, and text-to-SQL models. Cardinality/cost estimation is classified into supervised and unsupervised methods based on learning models, with illustrative examples provided to explain the working mechanisms. Detailed descriptions of various query optimizers are also given to elucidate the working mechanisms of each component in learning query optimizers. Additionally, we discuss the challenges and development opportunities of learning query optimizers. The survey further explores text-to-SQL models, a new research area within AI4DB. Finally, we consider the future development prospects of learning databases.