1
0
Fork 0
arangodb/arangod/Aql/SubqueryBlock.h

73 lines
2.2 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// 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.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Max Neunhoeffer
////////////////////////////////////////////////////////////////////////////////
#ifndef ARANGOD_AQL_SUBQUERY_BLOCK_H
#define ARANGOD_AQL_SUBQUERY_BLOCK_H 1
#include "Aql/ExecutionBlock.h"
#include "Aql/ExecutionNode.h"
namespace arangodb {
namespace aql {
class AqlItemBlock;
class ExecutionEngine;
class SubqueryBlock : public ExecutionBlock {
public:
SubqueryBlock(ExecutionEngine*, SubqueryNode const*, ExecutionBlock*);
~SubqueryBlock() = default;
/// @brief getSome
AqlItemBlock* getSome(size_t atMost) override final;
/// @brief shutdown, tell dependency and the subquery
int shutdown(int errorCode) override final;
/// @brief getter for the pointer to the subquery
ExecutionBlock* getSubquery() { return _subquery; }
private:
/// @brief execute the subquery and return its results
std::vector<AqlItemBlock*>* executeSubquery();
/// @brief destroy the results of a subquery
void destroySubqueryResults(std::vector<AqlItemBlock*>*);
/// @brief output register
RegisterId _outReg;
/// @brief we need to have an executionblock and where to write the result
ExecutionBlock* _subquery;
/// @brief whether the subquery is const and will always return the same values
/// when invoked multiple times
bool _subqueryIsConst;
};
} // namespace arangodb::aql
} // namespace arangodb
#endif