| // 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. |
| |
| #ifndef IMPALA_EXEC_SORT_NODE_H |
| #define IMPALA_EXEC_SORT_NODE_H |
| |
| #include "exec/exec-node.h" |
| #include "runtime/sorter.h" |
| |
| namespace impala { |
| |
| /// Node that implements a full sort of its input with a fixed memory budget, spilling |
| /// to disk if the input is larger than available memory. |
| /// Uses Sorter for the external sort implementation. |
| /// Input rows to SortNode are materialized by the Sorter into a single tuple |
| /// using the expressions specified in sort_tuple_exprs_. |
| /// In GetNext(), SortNode passes in the output batch to the sorter instance created |
| /// in Open() to fill it with sorted rows. |
| /// If a merge phase was performed in the sort, sorted rows are deep copied into |
| /// the output batch. Otherwise, the sorter instance owns the sorted data. |
| class SortNode : public ExecNode { |
| public: |
| SortNode(ObjectPool* pool, const TPlanNode& tnode, const DescriptorTbl& descs); |
| ~SortNode(); |
| |
| virtual Status Init(const TPlanNode& tnode, RuntimeState* state); |
| virtual Status Prepare(RuntimeState* state); |
| virtual void Codegen(RuntimeState* state); |
| virtual Status Open(RuntimeState* state); |
| virtual Status GetNext(RuntimeState* state, RowBatch* row_batch, bool* eos); |
| virtual Status Reset(RuntimeState* state, RowBatch* row_batch); |
| virtual void Close(RuntimeState* state); |
| |
| protected: |
| virtual void DebugString(int indentation_level, std::stringstream* out) const; |
| |
| private: |
| /// Fetch input rows and feed them to the sorter until the input is exhausted. |
| Status SortInput(RuntimeState* state) WARN_UNUSED_RESULT; |
| |
| /// Number of rows to skip. |
| int64_t offset_; |
| |
| /// Expressions and parameters used for tuple comparison. |
| std::vector<ScalarExpr*> ordering_exprs_; |
| |
| /// Expressions used to materialize slots in the tuples to be sorted. |
| /// One expr per slot in the materialized tuple. |
| std::vector<ScalarExpr*> sort_tuple_exprs_; |
| |
| std::vector<bool> is_asc_order_; |
| std::vector<bool> nulls_first_; |
| |
| /// Whether the previous call to GetNext() returned a buffer attached to the RowBatch. |
| /// Used to avoid unnecessary calls to ReleaseUnusedReservation(). |
| bool returned_buffer_ = false; |
| |
| ///////////////////////////////////////// |
| /// BEGIN: Members that must be Reset() |
| |
| /// Object used for external sorting. |
| boost::scoped_ptr<Sorter> sorter_; |
| |
| /// Keeps track of the number of rows skipped for handling offset_. |
| int64_t num_rows_skipped_; |
| |
| /// END: Members that must be Reset() |
| ///////////////////////////////////////// |
| }; |
| |
| } |
| |
| #endif |