ClickHouse/src/Storages/MergeTree/ReplicatedMergeTreePartHeader.h
2020-04-03 18:14:31 +03:00

51 lines
1.6 KiB
C++

#pragma once
#include <Storages/MergeTree/MergeTreeDataPartChecksum.h>
#include <Core/Types.h>
#include <IO/WriteBuffer.h>
#include <IO/ReadBuffer.h>
#include <IO/Operators.h>
#include <array>
namespace DB
{
class NamesAndTypesList;
/// This class provides a compact representation of part metadata (available columns and checksums)
/// that is intended to be stored in the part znode in ZooKeeper.
/// It can also be initialized from the legacy format (from the contents of separate <part>/columns
/// and <part>/checksums znodes).
class ReplicatedMergeTreePartHeader
{
public:
ReplicatedMergeTreePartHeader() = default;
static ReplicatedMergeTreePartHeader fromColumnsAndChecksumsZNodes(
const String & columns_znode, const String & checksums_znode);
static ReplicatedMergeTreePartHeader fromColumnsAndChecksums(
const NamesAndTypesList & columns, const MergeTreeDataPartChecksums & full_checksums);
void read(ReadBuffer & in);
static ReplicatedMergeTreePartHeader fromString(const String & str);
void write(WriteBuffer & out) const;
String toString() const;
const std::array<char, 16> & getColumnsHash() const { return columns_hash; }
const MinimalisticDataPartChecksums & getChecksums() const { return checksums; }
private:
ReplicatedMergeTreePartHeader(std::array<char, 16> columns_hash_, MinimalisticDataPartChecksums checksums_)
: columns_hash(std::move(columns_hash_)), checksums(std::move(checksums_))
{
}
std::array<char, 16> columns_hash;
MinimalisticDataPartChecksums checksums;
};
}