remove old algo.

planner/core/rule_join_reorder_dp.go

@@ -19,6 +19,7 @@ import (
 	"github.com/pingcap/parser/ast"
 	"github.com/pingcap/tidb/expression"
 	"github.com/pingcap/tidb/sessionctx"
+	log "github.com/sirupsen/logrus"
 )
 
 type joinReorderDPSolver struct {
@@ -179,3 +180,13 @@ func (s *joinReorderDPSolver) makeBushyJoin(cartesianJoinGroup []LogicalPlan) Lo
 	}
 	return cartesianJoinGroup[0]
 }
+
+func findNodeIndexInGroup(groups []LogicalPlan, col *expression.Column) int {
+	for i, plan := range groups {
+		if plan.Schema().Contains(col) {
+			return i
+		}
+	}
+	log.Errorf("Unknown columns %s, position %d", col, col.UniqueID)
+	return -1
+}

planner/core/rule_predicate_push_down.go

@@ -96,15 +96,6 @@ func (p *LogicalTableDual) PredicatePushDown(predicates []expression.Expression)
 // PredicatePushDown implements LogicalPlan PredicatePushDown interface.
 func (p *LogicalJoin) PredicatePushDown(predicates []expression.Expression) (ret []expression.Expression, retPlan LogicalPlan) {
 	simplifyOuterJoin(p, predicates)
-	/*
-		joinGroup := getCartesianJoinGroup(p)
-		if joinGroup != nil {
-			e := joinReOrderSolver{ctx: p.ctx}
-			e.reorderJoin(joinGroup, predicates)
-			newJoin := e.resultJoin
-			return newJoin.PredicatePushDown(predicates)
-		}
-	*/
 	leftPlan := p.children[0]
 	rightPlan := p.children[1]
 	var equalCond []*expression.ScalarFunction