ClickHouse/src/Storages/MergeTree/IMergeTreeDataPartWriter.h

#pragma once

#include <IO/WriteBufferFromFile.h>
#include <IO/WriteBufferFromFileBase.h>
#include <Compression/CompressedWriteBuffer.h>
#include <IO/HashingWriteBuffer.h>
#include <Storages/MergeTree/MergeTreeData.h>
#include <Storages/MergeTree/IMergeTreeDataPart.h>
#include <Disks/IDisk.h>


namespace DB
{

Block getBlockAndPermute(const Block & block, const Names & names, const IColumn::Permutation * permutation);

Block permuteBlockIfNeeded(const Block & block, const IColumn::Permutation * permutation);

/// 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 MergeTreeMutableDataPartPtr & data_part_,
        const NamesAndTypesList & columns_list_,
        const StorageMetadataPtr & metadata_snapshot_,
        const MergeTreeWriterSettings & settings_,
        const MergeTreeIndexGranularity & index_granularity_ = {});

    virtual ~IMergeTreeDataPartWriter();

    virtual void write(const Block & block, const IColumn::Permutation * permutation) = 0;

    virtual void fillChecksums(IMergeTreeDataPart::Checksums & checksums) = 0;

    virtual void finish(bool sync) = 0;

    Columns releaseIndexColumns();
    const MergeTreeIndexGranularity & getIndexGranularity() const { return index_granularity; }

protected:

    const MergeTreeMutableDataPartPtr data_part;
    const MergeTreeData & storage;
    const StorageMetadataPtr metadata_snapshot;
    const NamesAndTypesList columns_list;
    const MergeTreeWriterSettings settings;
    MergeTreeIndexGranularity index_granularity;
    const bool with_final_mark;

    MutableColumns index_columns;
};

}