Merge branch 'master' into indexjoin-enhancement

pingcap · Dec 13, 2018 · ff45b3f · ff45b3f
2 parents 7d5c4df + 2e95ee2
commit ff45b3f
Showing 1 changed file with 19 additions and 12 deletions.
diff --git a/planner/core/rule_join_reorder_greedy.go b/planner/core/rule_join_reorder_greedy.go
@@ -49,6 +49,9 @@ func extractJoinGroup(p LogicalPlan) (group []LogicalPlan, eqEdges []*expression
 }
 
 type joinReOrderGreedySolver struct {
+}
+
+type joinReorderGreedySingleGroupSolver struct {
 	ctx          sessionctx.Context
 	curJoinGroup []LogicalPlan
 	eqEdges      []*expression.ScalarFunction
@@ -67,7 +70,7 @@ type joinReOrderGreedySolver struct {
 //
 // For the nodes and join trees which don't have a join equal condition to
 // connect them, we make a bushy join tree to do the cartesian joins finally.
-func (s *joinReOrderGreedySolver) solve() (LogicalPlan, error) {
+func (s *joinReorderGreedySingleGroupSolver) solve() (LogicalPlan, error) {
 	for _, node := range s.curJoinGroup {
 		_, err := node.deriveStats()
 		if err != nil {
@@ -90,7 +93,7 @@ func (s *joinReOrderGreedySolver) solve() (LogicalPlan, error) {
 	return s.makeBushyJoin(cartesianGroup), nil
 }
 
-func (s *joinReOrderGreedySolver) constructConnectedJoinTree() (LogicalPlan, error) {
+func (s *joinReorderGreedySingleGroupSolver) constructConnectedJoinTree() (LogicalPlan, error) {
 	curJoinTree := s.curJoinGroup[0]
 	s.curJoinGroup = s.curJoinGroup[1:]
 	for {
@@ -126,7 +129,7 @@ func (s *joinReOrderGreedySolver) constructConnectedJoinTree() (LogicalPlan, err
 	return curJoinTree, nil
 }
 
-func (s *joinReOrderGreedySolver) checkConnectionAndMakeJoin(leftNode, rightNode LogicalPlan) (LogicalPlan, []expression.Expression) {
+func (s *joinReorderGreedySingleGroupSolver) checkConnectionAndMakeJoin(leftNode, rightNode LogicalPlan) (LogicalPlan, []expression.Expression) {
 	var usedEdges []*expression.ScalarFunction
 	remainOtherConds := make([]expression.Expression, len(s.otherConds))
 	copy(remainOtherConds, s.otherConds)
@@ -159,7 +162,7 @@ func (s *joinReOrderGreedySolver) checkConnectionAndMakeJoin(leftNode, rightNode
 	return newJoin, remainOtherConds
 }
 
-func (s *joinReOrderGreedySolver) makeBushyJoin(cartesianJoinGroup []LogicalPlan) LogicalPlan {
+func (s *joinReorderGreedySingleGroupSolver) makeBushyJoin(cartesianJoinGroup []LogicalPlan) LogicalPlan {
 	resultJoinGroup := make([]LogicalPlan, 0, (len(cartesianJoinGroup)+1)/2)
 	for len(cartesianJoinGroup) > 1 {
 		resultJoinGroup = resultJoinGroup[:0]
@@ -183,7 +186,7 @@ func (s *joinReOrderGreedySolver) makeBushyJoin(cartesianJoinGroup []LogicalPlan
 	return cartesianJoinGroup[0]
 }
 
-func (s *joinReOrderGreedySolver) newCartesianJoin(lChild, rChild LogicalPlan) *LogicalJoin {
+func (s *joinReorderGreedySingleGroupSolver) newCartesianJoin(lChild, rChild LogicalPlan) *LogicalJoin {
 	join := LogicalJoin{
 		JoinType:  InnerJoin,
 		reordered: true,
@@ -194,30 +197,34 @@ func (s *joinReOrderGreedySolver) newCartesianJoin(lChild, rChild LogicalPlan) *
 }
 
 func (s *joinReOrderGreedySolver) optimize(p LogicalPlan) (LogicalPlan, error) {
-	s.ctx = p.context()
-	return s.optimizeRecursive(p)
+	return s.optimizeRecursive(p.context(), p)
 }
 
-func (s *joinReOrderGreedySolver) optimizeRecursive(p LogicalPlan) (LogicalPlan, error) {
+func (s *joinReOrderGreedySolver) optimizeRecursive(ctx sessionctx.Context, p LogicalPlan) (LogicalPlan, error) {
 	var err error
 	curJoinGroup, eqEdges, otherConds := extractJoinGroup(p)
 	if len(curJoinGroup) > 1 {
 		for i := range curJoinGroup {
-			curJoinGroup[i], err = s.optimizeRecursive(curJoinGroup[i])
+			curJoinGroup[i], err = s.optimizeRecursive(ctx, curJoinGroup[i])
 			if err != nil {
 				return nil, err
 			}
 		}
-		s.curJoinGroup, s.eqEdges, s.otherConds = curJoinGroup, eqEdges, otherConds
-		p, err = s.solve()
+		groupSolver := &joinReorderGreedySingleGroupSolver{
+			ctx:          ctx,
+			curJoinGroup: curJoinGroup,
+			eqEdges:      eqEdges,
+			otherConds:   otherConds,
+		}
+		p, err = groupSolver.solve()
 		if err != nil {
 			return nil, err
 		}
 		return p, nil
 	}
 	newChildren := make([]LogicalPlan, 0, len(p.Children()))
 	for _, child := range p.Children() {
-		newChild, err := s.optimizeRecursive(child)
+		newChild, err := s.optimizeRecursive(ctx, child)
 		if err != nil {
 			return nil, err
 		}