“How Good Are Learned Cost Models?” Accepted to SIGMOD'25
2025/02/04
How Good Are Learned Cost Models, Really? Insights from Query Optimization Tasks
Authors: Roman Heinrich, Manisha Luthra, Johannes Wehrstein, Harald Kornmeyer, Carsten Binnig
Paper accepted to SIGMOD'25: “How Good Are Learned Cost Models, Really? Insights from Query Optimization Tasks”
Learned Cost Models like Zero-Shot and DACE typically predict the costs of executing a query plan more accurately than traditional cost models. But does this actually translate into selecting better query plans? We evaluate how recent LCMs affect query optimization and surprisingly find that classical models often still outperform LCMs. Based on our insights, we provide recommendations for making LCMs more effective for query optimization.