From 90de8791f5ca38184dc123ae596fe71633799438 Mon Sep 17 00:00:00 2001 From: Jussi Saurio Date: Sat, 10 May 2025 00:27:48 +0300 Subject: [PATCH] comments --- core/translate/optimizer.rs | 3 +++ 1 file changed, 3 insertions(+) diff --git a/core/translate/optimizer.rs b/core/translate/optimizer.rs index 6fd0855ee..21105b7ec 100644 --- a/core/translate/optimizer.rs +++ b/core/translate/optimizer.rs @@ -119,8 +119,11 @@ struct JoinN { pub cost: Cost, } +/// In lieu of statistics, we estimate that an equality filter will reduce the output set to 1% of its size. const SELECTIVITY_EQ: f64 = 0.01; +/// In lieu of statistics, we estimate that a range filter will reduce the output set to 40% of its size. const SELECTIVITY_RANGE: f64 = 0.4; +/// In lieu of statistics, we estimate that other filters will reduce the output set to 90% of its size. const SELECTIVITY_OTHER: f64 = 0.9; /// Join n-1 tables with the n'th table.