Query optimizers rely on accurate cardinality estimates to produce good execution plans. Despite decades of research, existing cardinality estimators are inaccurate for complex …
Cardinality estimation (CardEst) plays a significant role in generating high-quality query plans for a query optimizer in DBMS. In the last decade, an increasing number of advanced …
X Wang, C Qu, W Wu, J Wang, Q Zhou - arXiv preprint arXiv:2012.06743, 2020 - arxiv.org
Cardinality estimation is a fundamental but long unresolved problem in query optimization. Recently, multiple papers from different research groups consistently report that learned …
We explore the idea of using deep reinforcement learning for query optimization. The approach is to build queries incrementally by encoding properties of subqueries using a …
H Lan, Z Bao, Y Peng - Data Science and Engineering, 2021 - Springer
Query optimizer is at the heart of the database systems. Cost-based optimizer studied in this paper is adopted in almost all current database systems. A cost-based optimizer introduces …
Selectivity estimation-the problem of estimating the result size of queries-is a fundamental problem in databases. Accurate estimation of query selectivity involving multiple correlated …
Query optimizers rely on accurate cardinality estimation (CardEst) to produce good execution plans. The core problem of CardEst is how to model the rich joint distribution of …
J Wang, C Chai, J Liu, G Li - Proceedings of the VLDB Endowment, 2021 - dl.acm.org
Cardinality estimation is one of the most important problems in query optimization. Recently, machine learning based techniques have been proposed to effectively estimate cardinality …
Cardinality estimation is core to the query optimizers of DBMSs. Non-learned methods, especially based on histograms and samplings, have been widely used in commercial and …