https://yaooqinn.github.io/tags/join-order/ Recent content in Join-Order on Kent Yao Hugo -- 0.157.0 en-us Mon, 25 May 2026 00:00:00 +0000 https://yaooqinn.github.io/posts/spark/llm-for-join-order-an-apache-spark-perspective/ Mon, 25 May 2026 00:00:00 +0000 https://yaooqinn.github.io/posts/spark/llm-for-join-order-an-apache-spark-perspective/ Databricks and UPenn put an LLM agent to work as an offline join-order tuner and got P90 latency down 41% / geomean 1.288× speedup on JOB’s 113 queries — beating even perfect cardinality estimates. From the trenches of an open-source query engine, here is what that result does and does not prove.