| /** |
| * Copyright 2011-2015 Quickstep Technologies LLC. |
| * Copyright 2015 Pivotal Software, Inc. |
| * |
| * Licensed 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. |
| **/ |
| |
| #ifndef QUICKSTEP_EXPRESSIONS_PREDICATE_TRIVIAL_PREDICATES_HPP_ |
| #define QUICKSTEP_EXPRESSIONS_PREDICATE_TRIVIAL_PREDICATES_HPP_ |
| |
| #include "catalog/CatalogTypedefs.hpp" |
| #include "expressions/Expressions.pb.h" |
| #include "expressions/predicate/Predicate.hpp" |
| #include "storage/StorageBlockInfo.hpp" |
| #include "utility/Macros.hpp" |
| |
| namespace quickstep { |
| |
| class TupleIdSequence; |
| class ValueAccessor; |
| |
| struct SubBlocksReference; |
| |
| /** \addtogroup Expressions |
| * @{ |
| */ |
| |
| /** |
| * @brief Base class for trivial predicates which always evaluate to the same value. |
| **/ |
| class TrivialPredicate : public Predicate { |
| public: |
| bool hasStaticResult() const override { |
| return true; |
| } |
| |
| protected: |
| TrivialPredicate() { |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(TrivialPredicate); |
| }; |
| |
| /** |
| * @brief Predicate which always evaluates to true. |
| **/ |
| class TruePredicate : public TrivialPredicate { |
| public: |
| TruePredicate() { |
| } |
| |
| serialization::Predicate getProto() const override { |
| serialization::Predicate proto; |
| proto.set_predicate_type(serialization::Predicate::TRUE); |
| |
| return proto; |
| } |
| |
| Predicate* clone() const override { |
| return new TruePredicate(); |
| } |
| |
| PredicateType getPredicateType() const override { |
| return kTrue; |
| } |
| |
| bool matchesForSingleTuple(const ValueAccessor &accessor, |
| const tuple_id tuple) const override { |
| return true; |
| } |
| |
| bool matchesForJoinedTuples( |
| const ValueAccessor &left_accessor, |
| const relation_id left_relation_id, |
| const tuple_id left_tuple_id, |
| const ValueAccessor &right_accessor, |
| const relation_id right_relation_id, |
| const tuple_id right_tuple_id) const override { |
| return true; |
| } |
| |
| TupleIdSequence* getAllMatches(ValueAccessor *accessor, |
| const SubBlocksReference *sub_blocks_ref, |
| const TupleIdSequence *filter, |
| const TupleIdSequence *existence_map) const override { |
| return GenerateSequenceForStaticResult(accessor, filter, existence_map, true); |
| } |
| |
| bool getStaticResult() const override { |
| return true; |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(TruePredicate); |
| }; |
| |
| /** |
| * @brief Predicate which always evaluates to false. |
| **/ |
| class FalsePredicate : public TrivialPredicate { |
| public: |
| FalsePredicate() { |
| } |
| |
| serialization::Predicate getProto() const override { |
| serialization::Predicate proto; |
| proto.set_predicate_type(serialization::Predicate::FALSE); |
| |
| return proto; |
| } |
| |
| Predicate* clone() const override { |
| return new FalsePredicate(); |
| } |
| |
| PredicateType getPredicateType() const override { |
| return kFalse; |
| } |
| |
| bool matchesForSingleTuple(const ValueAccessor &accessor, |
| const tuple_id tuple) const override { |
| return false; |
| } |
| |
| bool matchesForJoinedTuples( |
| const ValueAccessor &left_accessor, |
| const relation_id left_relation_id, |
| const tuple_id left_tuple_id, |
| const ValueAccessor &right_accessor, |
| const relation_id right_relation_id, |
| const tuple_id right_tuple_id) const override { |
| return false; |
| } |
| |
| TupleIdSequence* getAllMatches(ValueAccessor *accessor, |
| const SubBlocksReference *sub_blocks_ref, |
| const TupleIdSequence *filter, |
| const TupleIdSequence *existence_map) const override { |
| return GenerateSequenceForStaticResult(accessor, filter, existence_map, false); |
| } |
| |
| bool getStaticResult() const override { |
| return false; |
| } |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(FalsePredicate); |
| }; |
| |
| /** @} */ |
| |
| } // namespace quickstep |
| |
| #endif // QUICKSTEP_EXPRESSIONS_PREDICATE_TRIVIAL_PREDICATES_HPP_ |