ClickHouse/src/Storages/MergeTree/MergeTreeDataPartWide.h
Azat Khuzhin 22e44ced8a Add column modification time into system.parts_columns
This can be useful to obtain at least some time for the part after
mutations, since mutations will change the modification time of all
parts.

Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
2023-07-03 13:34:05 +02:00

77 lines
2.9 KiB
C++

#pragma once
#include "Storages/MergeTree/IDataPartStorage.h"
#include <Storages/MergeTree/IMergeTreeDataPart.h>
namespace DB
{
/** In wide format data of each column is stored in one or several (for complex types) files.
* Every data file is followed by marks file.
* Can be used in tables with both adaptive and non-adaptive granularity.
* This is the regular format of parts for MergeTree and suitable for big parts, as it's the most efficient.
* Data part would be created in wide format if it's uncompressed size in bytes or number of rows would exceed
* thresholds `min_bytes_for_wide_part` and `min_rows_for_wide_part`.
*/
class MergeTreeDataPartWide : public IMergeTreeDataPart
{
public:
MergeTreeDataPartWide(
const MergeTreeData & storage_,
const String & name_,
const MergeTreePartInfo & info_,
const MutableDataPartStoragePtr & data_part_storage_,
const IMergeTreeDataPart * parent_part_ = nullptr);
MergeTreeReaderPtr getReader(
const NamesAndTypesList & columns,
const StorageMetadataPtr & metadata_snapshot,
const MarkRanges & mark_ranges,
UncompressedCache * uncompressed_cache,
MarkCache * mark_cache,
const AlterConversionsPtr & alter_conversions,
const MergeTreeReaderSettings & reader_settings_,
const ValueSizeMap & avg_value_size_hints,
const ReadBufferFromFileBase::ProfileCallback & profile_callback) const override;
MergeTreeWriterPtr getWriter(
const NamesAndTypesList & columns_list,
const StorageMetadataPtr & metadata_snapshot,
const std::vector<MergeTreeIndexPtr> & indices_to_recalc,
const CompressionCodecPtr & default_codec_,
const MergeTreeWriterSettings & writer_settings,
const MergeTreeIndexGranularity & computed_index_granularity) override;
bool isStoredOnDisk() const override { return true; }
bool isStoredOnRemoteDisk() const override;
bool isStoredOnRemoteDiskWithZeroCopySupport() const override;
String getFileNameForColumn(const NameAndTypePair & column) const override;
~MergeTreeDataPartWide() override;
bool hasColumnFiles(const NameAndTypePair & column) const override;
std::optional<time_t> getColumnModificationTime(const String & column_name) const override;
protected:
static void loadIndexGranularityImpl(
MergeTreeIndexGranularity & index_granularity_, MergeTreeIndexGranularityInfo & index_granularity_info_,
const IDataPartStorage & data_part_storage_, const std::string & any_column_file_name);
private:
void checkConsistency(bool require_part_metadata) const override;
/// Loads marks index granularity into memory
void loadIndexGranularity() override;
ColumnSize getColumnSizeImpl(const NameAndTypePair & column, std::unordered_set<String> * processed_substreams) const;
void calculateEachColumnSizes(ColumnSizeByName & each_columns_size, ColumnSize & total_size) const override;
};
}