Method backupData

src/Storages/StorageMergeTree.cpp:3143–3171

void StorageMergeTree::backupData(BackupEntriesCollector & backup_entries_collector, const String & data_path_in_backup, const std::optional<ASTs> & partitions)
{
    const auto & backup_settings = backup_entries_collector.getBackupSettings();
    auto local_context = backup_entries_collector.getContext();

    /// TODO(unique-key): sidecar-aware backup. The per-part delete-bitmap
    /// sidecars are not enumerated as part artifacts, so BACKUP would silently
    /// omit them and restore would resurrect deleted rows. Reject for now.
    if (auto uk_metadata = getInMemoryMetadataPtr(local_context, false); uk_metadata && uk_metadata->hasUniqueKey())
        throw Exception(ErrorCodes::SUPPORT_IS_DISABLED,
            "BACKUP is not supported for UNIQUE KEY tables yet: delete-bitmap sidecars "
            "are not preserved across backup/restore.");

    DataPartsVector data_parts;
    if (partitions)
        data_parts = getVisibleDataPartsVectorInPartitions(local_context, getPartitionIDsFromQuery(*partitions, local_context));
    else
        data_parts = getVisibleDataPartsVector(local_context);

    Int64 min_data_version = std::numeric_limits<Int64>::max();
    for (const auto & data_part : data_parts)
        min_data_version = std::min(min_data_version, data_part->info.getDataVersion() + 1);

    auto parts_backup_entries = backupParts(data_parts, data_path_in_backup, backup_settings, local_context);
    for (auto & part_backup_entries : parts_backup_entries)
        backup_entries_collector.addBackupEntries(std::move(part_backup_entries.backup_entries));

    backup_entries_collector.addBackupEntries(backupMutations(min_data_version, data_path_in_backup));
}


BackupEntries StorageMergeTree::backupMutations(UInt64 version, const String & data_path_in_backup) const