| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| **/ |
| |
| #include "query_optimizer/expressions/SimpleCase.hpp" |
| |
| #include <cstddef> |
| #include <memory> |
| #include <string> |
| #include <unordered_map> |
| #include <utility> |
| #include <vector> |
| |
| #include "expressions/predicate/Predicate.hpp" |
| #include "expressions/scalar/ScalarCaseExpression.hpp" |
| #include "expressions/scalar/ScalarLiteral.hpp" |
| #include "query_optimizer/OptimizerTree.hpp" |
| #include "query_optimizer/expressions/AttributeReference.hpp" |
| #include "query_optimizer/expressions/ComparisonExpression.hpp" |
| #include "query_optimizer/expressions/Expression.hpp" |
| #include "query_optimizer/expressions/PatternMatcher.hpp" |
| #include "query_optimizer/expressions/Predicate.hpp" |
| #include "query_optimizer/expressions/Scalar.hpp" |
| #include "types/Type.hpp" |
| #include "types/operations/comparisons/ComparisonID.hpp" |
| #include "types/operations/comparisons/ComparisonFactory.hpp" |
| #include "utility/Cast.hpp" |
| #include "utility/HashPair.hpp" |
| |
| #include "glog/logging.h" |
| |
| namespace quickstep { |
| namespace optimizer { |
| namespace expressions { |
| |
| // We treat a SimpleCase as constant only if all operands are constant. |
| bool SimpleCase::isConstant() const { |
| if (!case_operand_->isConstant()) { |
| return false; |
| } |
| for (const ScalarPtr &condition_operand : condition_operands_) { |
| if (!condition_operand->isConstant()) { |
| return false; |
| } |
| } |
| for (const ScalarPtr &conditional_result_expression : conditional_result_expressions_) { |
| if (!conditional_result_expression->isConstant()) { |
| return false; |
| } |
| } |
| return (else_result_expression_ == nullptr || else_result_expression_->isConstant()); |
| } |
| |
| std::vector<AttributeReferencePtr> SimpleCase::getReferencedAttributes() const { |
| std::vector<AttributeReferencePtr> referenced_attributes; |
| |
| const std::vector<AttributeReferencePtr> referenced_attributes_in_case_operand = |
| case_operand_->getReferencedAttributes(); |
| referenced_attributes.insert(referenced_attributes.end(), |
| referenced_attributes_in_case_operand.begin(), |
| referenced_attributes_in_case_operand.end()); |
| |
| for (const ScalarPtr &condition_operand : condition_operands_) { |
| const std::vector<AttributeReferencePtr> referenced_attributes_in_condition_operand = |
| condition_operand->getReferencedAttributes(); |
| referenced_attributes.insert(referenced_attributes.end(), |
| referenced_attributes_in_condition_operand.begin(), |
| referenced_attributes_in_condition_operand.end()); |
| } |
| for (const ScalarPtr &conditional_result_expression : conditional_result_expressions_) { |
| const std::vector<AttributeReferencePtr> referenced_attributes_in_conditional_result_expression = |
| conditional_result_expression->getReferencedAttributes(); |
| referenced_attributes.insert(referenced_attributes.end(), |
| referenced_attributes_in_conditional_result_expression.begin(), |
| referenced_attributes_in_conditional_result_expression.end()); |
| } |
| if (else_result_expression_ != nullptr) { |
| const std::vector<AttributeReferencePtr> referenced_attributes_in_else_result_expression = |
| else_result_expression_->getReferencedAttributes(); |
| referenced_attributes.insert(referenced_attributes.end(), |
| referenced_attributes_in_else_result_expression.begin(), |
| referenced_attributes_in_else_result_expression.end()); |
| } |
| |
| return referenced_attributes; |
| } |
| |
| ExpressionPtr SimpleCase::copyWithNewChildren(const std::vector<ExpressionPtr> &new_children) const { |
| DCHECK_EQ(getNumChildren(), new_children.size()); |
| |
| ScalarPtr new_case_operand; |
| std::vector<ScalarPtr> new_condition_operands; |
| std::vector<ScalarPtr> new_conditional_result_expressions; |
| ScalarPtr new_else_result_expression; |
| |
| new_condition_operands.reserve(condition_operands_.size()); |
| new_conditional_result_expressions.reserve(condition_operands_.size()); |
| |
| new_case_operand = std::static_pointer_cast<const Scalar>(new_children[0]); |
| std::size_t num_when_clauses = condition_operands_.size(); |
| for (std::size_t index = 1; index <= num_when_clauses; ++index) { |
| new_condition_operands.push_back( |
| std::static_pointer_cast<const Scalar>(new_children[index])); |
| |
| new_conditional_result_expressions.push_back( |
| std::static_pointer_cast<const Scalar>(new_children[index + num_when_clauses])); |
| } |
| if (else_result_expression_ != nullptr) { |
| new_else_result_expression = |
| std::static_pointer_cast<const Scalar>(new_children.back()); |
| } |
| |
| return Create(new_case_operand, |
| new_condition_operands, |
| new_conditional_result_expressions, |
| new_else_result_expression, |
| value_type_); |
| } |
| |
| ::quickstep::Scalar* SimpleCase::concretize( |
| const std::unordered_map<ExprId, const CatalogAttribute*> &substitution_map) const { |
| std::vector<std::unique_ptr<quickstep::Predicate>> when_predicates; |
| for (const ScalarPtr &condition_operand : condition_operands_) { |
| const PredicatePtr predicate = |
| ComparisonExpression::Create( |
| quickstep::ComparisonFactory::GetComparison(quickstep::ComparisonID::kEqual), |
| case_operand_, |
| condition_operand); |
| when_predicates.emplace_back(predicate->concretize(substitution_map)); |
| } |
| |
| std::vector<std::unique_ptr<quickstep::Scalar>> result_expressions; |
| for (const ScalarPtr &expression : conditional_result_expressions_) { |
| result_expressions.emplace_back(expression->concretize(substitution_map)); |
| } |
| |
| std::unique_ptr<quickstep::Scalar> else_result_expression; |
| if (else_result_expression_ == nullptr) { |
| else_result_expression.reset( |
| new quickstep::ScalarLiteral(value_type_.makeNullValue(), value_type_)); |
| } else { |
| else_result_expression.reset( |
| else_result_expression_->concretize(substitution_map)); |
| } |
| |
| return new quickstep::ScalarCaseExpression( |
| value_type_, |
| std::move(when_predicates), |
| std::move(result_expressions), |
| else_result_expression.release()); |
| } |
| |
| std::size_t SimpleCase::computeHash() const { |
| std::size_t hash_code = |
| CombineHashes(static_cast<std::size_t>(ExpressionType::kSimpleCase), |
| case_operand_->hash()); |
| for (std::size_t i = 0; i < condition_operands_.size(); ++i) { |
| hash_code = CombineHashes(hash_code, condition_operands_[i]->hash()); |
| hash_code = CombineHashes(hash_code, conditional_result_expressions_[i]->hash()); |
| } |
| if (else_result_expression_ != nullptr) { |
| hash_code = CombineHashes(hash_code, else_result_expression_->hash()); |
| } |
| return hash_code; |
| } |
| |
| bool SimpleCase::equals(const ScalarPtr &other) const { |
| SimpleCasePtr expr; |
| if (!SomeSimpleCase::MatchesWithConditionalCast(other, &expr)) { |
| return false; |
| } |
| if (!case_operand_->equals(expr->case_operand_)) { |
| return false; |
| } |
| if (condition_operands_.size() != expr->condition_operands_.size()) { |
| return false; |
| } |
| for (std::size_t i = 0; i < condition_operands_.size(); ++i) { |
| if (!condition_operands_[i]->equals(expr->condition_operands_[i]) |
| || !conditional_result_expressions_[i]->equals( |
| expr->conditional_result_expressions_[i])) { |
| return false; |
| } |
| } |
| if (else_result_expression_ == nullptr || expr->else_result_expression_ == nullptr) { |
| return else_result_expression_ == expr->else_result_expression_; |
| } |
| if (!else_result_expression_->equals(expr->else_result_expression_)) { |
| return false; |
| } |
| DCHECK(value_type_.equals(expr->value_type_)); |
| return true; |
| } |
| |
| void SimpleCase::getFieldStringItems( |
| std::vector<std::string> *inline_field_names, |
| std::vector<std::string> *inline_field_values, |
| std::vector<std::string> *non_container_child_field_names, |
| std::vector<OptimizerTreeBaseNodePtr> *non_container_child_fields, |
| std::vector<std::string> *container_child_field_names, |
| std::vector<std::vector<OptimizerTreeBaseNodePtr>> *container_child_fields) const { |
| non_container_child_field_names->push_back("case_operand"); |
| non_container_child_fields->push_back(case_operand_); |
| |
| container_child_field_names->push_back("condition_operands"); |
| container_child_fields->push_back(CastSharedPtrVector<OptimizerTreeBase>(condition_operands_)); |
| |
| container_child_field_names->push_back("result_expressions"); |
| container_child_fields->push_back(CastSharedPtrVector<OptimizerTreeBase>(conditional_result_expressions_)); |
| |
| if (else_result_expression_ != nullptr) { |
| non_container_child_field_names->push_back("else_result_expression"); |
| non_container_child_fields->push_back(else_result_expression_); |
| } |
| } |
| |
| } // namespace expressions |
| } // namespace optimizer |
| } // namespace quickstep |