ClickHouse/src/Storages/MergeTree/IMergeTreeDataPartWriter.h
2020-09-01 18:53:22 +03:00

91 lines
3.3 KiB
C++

#pragma once
#include <IO/WriteBufferFromFile.h>
#include <IO/WriteBufferFromFileBase.h>
#include <Compression/CompressedWriteBuffer.h>
#include <IO/HashingWriteBuffer.h>
#include <Storages/MergeTree/MergeTreeData.h>
#include <DataStreams/IBlockOutputStream.h>
#include <Storages/MergeTree/IMergeTreeDataPart.h>
#include <Disks/IDisk.h>
namespace DB
{
/// Writes data part to disk in different formats.
/// Calculates and serializes primary and skip indices if needed.
class IMergeTreeDataPartWriter : private boost::noncopyable
{
public:
IMergeTreeDataPartWriter(
const MergeTreeData::DataPartPtr & data_part_,
const NamesAndTypesList & columns_list_,
const StorageMetadataPtr & metadata_snapshot_,
const MergeTreeWriterSettings & settings_);
IMergeTreeDataPartWriter(
const MergeTreeData::DataPartPtr & data_part_,
const NamesAndTypesList & columns_list_,
const StorageMetadataPtr & metadata_snapshot_,
const MergeTreeIndices & skip_indices_,
const MergeTreeIndexGranularity & index_granularity_,
const MergeTreeWriterSettings & settings_);
virtual ~IMergeTreeDataPartWriter();
virtual void write(
const Block & block, const IColumn::Permutation * permutation = nullptr,
/* Blocks with already sorted index columns */
const Block & primary_key_block = {}, const Block & skip_indexes_block = {}) = 0;
virtual void calculateAndSerializePrimaryIndex(const Block & /* primary_index_block */) {}
virtual void calculateAndSerializeSkipIndices(const Block & /* skip_indexes_block */) {}
/// Shift mark and offset to prepare read next mark.
/// You must call it after calling write method and optionally
/// calling calculations of primary and skip indices.
void next();
virtual void initSkipIndices() {}
virtual void initPrimaryIndex() {}
virtual void finishDataSerialization(IMergeTreeDataPart::Checksums & checksums, bool sync) = 0;
virtual void finishPrimaryIndexSerialization(MergeTreeData::DataPart::Checksums & /* checksums */, bool /* sync */) {}
virtual void finishSkipIndicesSerialization(MergeTreeData::DataPart::Checksums & /* checksums */, bool /* sync */) {}
Columns releaseIndexColumns();
const MergeTreeIndexGranularity & getIndexGranularity() const { return index_granularity; }
const MergeTreeIndices & getSkipIndices() { return skip_indices; }
protected:
size_t getCurrentMark() const { return current_mark; }
size_t getIndexOffset() const { return index_offset; }
using SerializationState = IDataType::SerializeBinaryBulkStatePtr;
using SerializationStates = std::unordered_map<String, SerializationState>;
MergeTreeData::DataPartPtr data_part;
const MergeTreeData & storage;
StorageMetadataPtr metadata_snapshot;
NamesAndTypesList columns_list;
MergeTreeIndices skip_indices;
MergeTreeIndexGranularity index_granularity;
MergeTreeWriterSettings settings;
bool with_final_mark;
size_t next_mark = 0;
size_t next_index_offset = 0;
MutableColumns index_columns;
private:
/// Data is already written up to this mark.
size_t current_mark = 0;
/// The offset to the first row of the block for which you want to write the index.
size_t index_offset = 0;
};
}