adjust coster to use seqIOCostFactor

angelamayxie · angelamayxie · commit cfb9c68c85d0 · 2025-07-25T13:50:30.000-07:00
diff --git a/sql/memo/coster.go b/sql/memo/coster.go
@@ -136,11 +136,11 @@ func (c *coster) costRel(ctx *sql.Context, n RelExpr, s sql.StatsProvider) (floa
 				expectedRightRows := selfJoinCard * matchRate
 
 				if expectedRightRows < lBest {
-					return lBest*(seqIOCostFactor) + (lBest + indexCoverageAdjustment(n.Lookup)*(cpuCostFactor+randIOCostFactor)), nil
+					return lBest*(seqIOCostFactor) + (lBest + indexCoverageAdjustment(n.Lookup)*(seqIOCostFactor+randIOCostFactor)), nil
 				}
 
 				// Estimate for reading each left row and each expected right row
-				return lBest*seqIOCostFactor + expectedRightRows*(cpuCostFactor+randIOCostFactor), nil
+				return lBest*seqIOCostFactor + expectedRightRows*(seqIOCostFactor+randIOCostFactor), nil
 			case *ConcatJoin:
 				return c.costConcatJoin(ctx, n, s)
 			}

Original file line number	Diff line number	Diff line change
`@@ -136,11 +136,11 @@ func (c coster) costRel(ctx sql.Context, n RelExpr, s sql.StatsProvider) (floa`
`136`	`136`	`expectedRightRows := selfJoinCard * matchRate`
`137`	`137`
`138`	`138`	`if expectedRightRows < lBest {`
`139`		`- return lBest(seqIOCostFactor) + (lBest + indexCoverageAdjustment(n.Lookup)(cpuCostFactor+randIOCostFactor)), nil`
	`139`	`+ return lBest(seqIOCostFactor) + (lBest + indexCoverageAdjustment(n.Lookup)(seqIOCostFactor+randIOCostFactor)), nil`
`140`	`140`	`}`
`141`	`141`
`142`	`142`	`// Estimate for reading each left row and each expected right row`
`143`		`- return lBestseqIOCostFactor + expectedRightRows(cpuCostFactor+randIOCostFactor), nil`
	`143`	`+ return lBestseqIOCostFactor + expectedRightRows(seqIOCostFactor+randIOCostFactor), nil`
`144`	`144`	`case *ConcatJoin:`
`145`	`145`	`return c.costConcatJoin(ctx, n, s)`
`146`	`146`	`}`