Address comments.

pingcap · Dec 27, 2019 · df53bfd · df53bfd
1 parent a9976ad
commit df53bfd
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Showing 2 changed files with 4 additions and 8 deletions.
diff --git a/planner/cascades/testdata/transformation_rules_suite_out.json b/planner/cascades/testdata/transformation_rules_suite_out.json
@@ -351,7 +351,7 @@
           "Group#0 Schema:[test.t.b]", 
           "    Projection_2 input:[Group#1], test.t.b", 
           "Group#1 Schema:[test.t.b]", 
-          "    Limit_6 input:[Group#2], offset:0, count:2", 
+          "    Limit_3 input:[Group#2], offset:0, count:2", 
           "Group#2 Schema:[test.t.b]", 
           "    TiKVSingleGather_5 input:[Group#3], table:t", 
           "Group#3 Schema:[test.t.b]", 

diff --git a/planner/cascades/transformation_rules.go b/planner/cascades/transformation_rules.go
@@ -671,7 +671,8 @@ type PushLimitDownProjection struct {
 	baseRule
 }
 
-// NewRulePushLimitDownProjection creates a new Transformation. The pattern of this rule is `Limit->Projection->X` to `Projection->Limit->X`.
+// NewRulePushLimitDownProjection creates a new Transformation.
+// The pattern of this rule is `Limit->Projection->X` to `Projection->Limit->X`.
 func NewRulePushLimitDownProjection() Transformation {
 	rule := &PushLimitDownProjection{}
 	rule.pattern = memo.BuildPattern(
@@ -700,13 +701,8 @@ func (r *PushLimitDownProjection) OnTransform(old *memo.ExprIter) (newExprs []*m
 	proj := old.Children[0].GetExpr().ExprNode.(*plannercore.LogicalProjection)
 	childGroup := old.Children[0].GetExpr().Children[0]
 
-	newLimit := plannercore.LogicalLimit{
-		Offset: limit.Offset,
-		Count:  limit.Count,
-	}.Init(limit.SCtx(), limit.SelectBlockOffset())
-
 	projExpr := memo.NewGroupExpr(proj)
-	limitExpr := memo.NewGroupExpr(newLimit)
+	limitExpr := memo.NewGroupExpr(limit)
 	limitExpr.SetChildren(childGroup)
 	limitGroup := memo.NewGroupWithSchema(limitExpr, childGroup.Prop.Schema)
 	projExpr.SetChildren(limitGroup)