[Video] Advanced SQL join table cardinality estimates

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We're happy to share a new video from our InterSystems Developers YouTube:

⏯  Advanced SQL join table cardinality estimates @ Ready 2025

Thomas Henchel presents his team’s recent work on improving cardinality estimates in SQL query optimizers - a key factor that affects join ordering and query performance. The team implemented a new state-of-the-art estimation method based on 2023 research. When tested on benchmark queries, most results showed no change, but around 21% of queries ran slower and only about 11% improved. These mixed results highlight challenges in balancing over- and underestimation. The group continues refining optimization techniques to achieve faster, more efficient queries and invites feedback on patterns or concerns from real workloads.

🗣 Presenter: @Thomas Hentschel, Systems Developer, InterSystems

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