rules.go 1.1 KB

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  1. // Copyright 2021 EMQ Technologies Co., Ltd.
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. //
  7. // http://www.apache.org/licenses/LICENSE-2.0
  8. //
  9. // Unless required by applicable law or agreed to in writing, software
  10. // distributed under the License is distributed on an "AS IS" BASIS,
  11. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. // See the License for the specific language governing permissions and
  13. // limitations under the License.
  14. package planner
  15. type logicalOptRule interface {
  16. optimize(LogicalPlan) (LogicalPlan, error)
  17. name() string
  18. }
  19. type predicatePushDown struct{}
  20. func (r *predicatePushDown) optimize(lp LogicalPlan) (LogicalPlan, error) {
  21. _, p := lp.PushDownPredicate(nil)
  22. return p, nil
  23. }
  24. func (r *predicatePushDown) name() string {
  25. return "predicatePushDown"
  26. }
  27. type columnPruner struct{}
  28. func (r *columnPruner) optimize(lp LogicalPlan) (LogicalPlan, error) {
  29. err := lp.PruneColumns(nil)
  30. return lp, err
  31. }
  32. func (r *columnPruner) name() string {
  33. return "columnPruner"
  34. }