#pragma once #include namespace Poco { class Path; } namespace DB { /** Creates a local (at the same mount point) backup (snapshot) directory. * * In the specified destination directory, it creates a hard links on all source-directory files * and in all nested directories, with saving (creating) all relative paths; * and also `chown`, removing the write permission. * * This protects data from accidental deletion or modification, * and is intended to be used as a simple means of protection against a human or program error, * but not from a hardware failure. * * If max_level is specified, than only files which depth relative source_path less or equal max_level will be copied. * So, if max_level=0 than only direct file child are copied. */ void localBackup(const Poco::Path & source_path, const Poco::Path & destination_path, std::optional max_level = {}); }