plan: tiny clean (pingcap#5169)

plan/column_pruning.go

@@ -282,15 +282,8 @@ func (p *SelectLock) PruneColumns(parentUsedCols []*expression.Column) {
 	if p.Lock != ast.SelectLockForUpdate {
 		p.baseLogicalPlan.PruneColumns(parentUsedCols)
 	} else {
-		used := getUsedList(parentUsedCols, p.schema)
 		for _, cols := range p.children[0].Schema().TblID2Handle {
-			for _, col := range cols {
-				col.ResolveIndices(p.children[0].Schema())
-				if !used[col.Index] {
-					used[col.Index] = true
-					parentUsedCols = append(parentUsedCols, col)
-				}
-			}
+			parentUsedCols = append(parentUsedCols, cols...)
 		}
 		p.children[0].(LogicalPlan).PruneColumns(parentUsedCols)
 	}

plan/physical_plans.go

@@ -112,7 +112,12 @@ func (p *PhysicalIndexLookUpReader) Copy() PhysicalPlan {
 
 // PhysicalIndexScan represents an index scan plan.
 type PhysicalIndexScan struct {
-	physicalTableSource
+	*basePlan
+	basePhysicalPlan
+
+	// AccessCondition is used to calculate range.
+	AccessCondition []expression.Expression
+	filterCondition []expression.Expression
 
 	Table      *model.TableInfo
 	Index      *model.IndexInfo
@@ -157,17 +162,6 @@ func (p *PhysicalMemTable) Copy() PhysicalPlan {
 	return &np
 }
 
-type physicalTableSource struct {
-	*basePlan
-	basePhysicalPlan
-
-	// AccessCondition is used to calculate range.
-	AccessCondition []expression.Expression
-
-	// filterCondition is only used by new planner.
-	filterCondition []expression.Expression
-}
-
 func needCount(af aggregation.Aggregation) bool {
 	return af.GetName() == ast.AggFuncCount || af.GetName() == ast.AggFuncAvg
 }
@@ -179,7 +173,12 @@ func needValue(af aggregation.Aggregation) bool {
 
 // PhysicalTableScan represents a table scan plan.
 type PhysicalTableScan struct {
-	physicalTableSource
+	*basePlan
+	basePhysicalPlan
+
+	// AccessCondition is used to calculate range.
+	AccessCondition []expression.Expression
+	filterCondition []expression.Expression
 
 	Table   *model.TableInfo
 	Columns []*model.ColumnInfo