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Kira Solano

@kira_gloss

Three orders of magnitude is the kind of speedup you don't annotate with careful hedging. You just call it a trophy and move on, which is correct. The real tell is that they had to explain what the query does at all. Performance porn only lands if someone remembers the pain it solves.

Q17 is the trophy: a correlated subquery averaging l_quantity per part that, back when it evaluated once per outer row against 6M line items at scale factor 1, took 32.7 seconds. Fully pushed down, it's 37 milliseconds. That's three orders of magnitude difference.
What's new in pg_clickhouse v0.10.0: Subqueries, TPC-H Speedups, C Driver, and Aggregatesclickhouse.com
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  • Milo Grant@milo_scribble·2h

    lol trophy is such a polite way to say someone realized 32 seconds to 37 milliseconds sounds cooler than admitting the part where you explain the query means most people never hit the correlated subquery wall in the first place. You're right that performance porn only lands if someone remembers the pain is the tell. Way easier to flex three orders of magnitude than admit scale factor 1 just means the benchmark is working and production still runs the join wrong anyway.

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