fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
85 lines
3.2 KiB
85 lines
3.2 KiB
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
//
|
|
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file. See the AUTHORS file for names of contributors.
|
|
|
|
#pragma once
|
|
|
|
#include "db/range_del_aggregator.h"
|
|
#include "rocksdb/slice.h"
|
|
#include "rocksdb/types.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
|
|
class Arena;
|
|
class ArenaWrappedDBIter;
|
|
class InternalKeyComparator;
|
|
|
|
template <class TValue>
|
|
class InternalIteratorBase;
|
|
using InternalIterator = InternalIteratorBase<Slice>;
|
|
|
|
// Return an iterator that provided the union of the data in
|
|
// children[0,n-1]. Takes ownership of the child iterators and
|
|
// will delete them when the result iterator is deleted.
|
|
//
|
|
// The result does no duplicate suppression. I.e., if a particular
|
|
// key is present in K child iterators, it will be yielded K times.
|
|
//
|
|
// REQUIRES: n >= 0
|
|
extern InternalIterator* NewMergingIterator(
|
|
const InternalKeyComparator* comparator, InternalIterator** children, int n,
|
|
Arena* arena = nullptr, bool prefix_seek_mode = false);
|
|
|
|
class MergingIterator;
|
|
|
|
// A builder class to build a merging iterator by adding iterators one by one.
|
|
class MergeIteratorBuilder {
|
|
public:
|
|
// comparator: the comparator used in merging comparator
|
|
// arena: where the merging iterator needs to be allocated from.
|
|
explicit MergeIteratorBuilder(const InternalKeyComparator* comparator,
|
|
Arena* arena, bool prefix_seek_mode = false);
|
|
~MergeIteratorBuilder();
|
|
|
|
// Add iter to the merging iterator.
|
|
void AddIterator(InternalIterator* iter);
|
|
|
|
// Add a range tombstone iterator to underlying merge iterator.
|
|
// See MergingIterator::AddRangeTombstoneIterator() for more detail.
|
|
//
|
|
// If `iter_ptr` is not nullptr, *iter_ptr will be set to where the merging
|
|
// iterator stores `iter` when MergeIteratorBuilder::Finish() is called. This
|
|
// is used by level iterator to update range tombstone iters when switching to
|
|
// a different SST file.
|
|
void AddRangeTombstoneIterator(
|
|
TruncatedRangeDelIterator* iter,
|
|
TruncatedRangeDelIterator*** iter_ptr = nullptr);
|
|
|
|
// Get arena used to build the merging iterator. It is called one a child
|
|
// iterator needs to be allocated.
|
|
Arena* GetArena() { return arena; }
|
|
|
|
// Return the result merging iterator.
|
|
// If db_iter is not nullptr, then db_iter->SetMemtableRangetombstoneIter()
|
|
// will be called with pointer to where the merging iterator
|
|
// stores the memtable range tombstone iterator.
|
|
// This is used for DB iterator to refresh memtable range tombstones.
|
|
InternalIterator* Finish(ArenaWrappedDBIter* db_iter = nullptr);
|
|
|
|
private:
|
|
MergingIterator* merge_iter;
|
|
InternalIterator* first_iter;
|
|
bool use_merging_iter;
|
|
Arena* arena;
|
|
// Used to set LevelIterator.range_tombstone_iter_.
|
|
// See AddRangeTombstoneIterator() implementation for more detail.
|
|
std::vector<std::pair<size_t, TruncatedRangeDelIterator***>>
|
|
range_del_iter_ptrs_;
|
|
};
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|
|
|