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system.backup_log

Querying in ClickHouse Cloud

The data in this system table is held locally on each node in ClickHouse Cloud. Obtaining a complete view of all data, therefore, requires the clusterAllReplicas function. See here for further details.

Contains logging entries with information about BACKUP and RESTORE operations.

Columns:

  • hostname (LowCardinality(String)) — Hostname of the server executing the query.
  • event_date (Date) — Date of the entry.
  • event_time (DateTime) — The date and time of the entry.
  • event_time_microseconds (DateTime64) — Time of the entry with microseconds precision.
  • id (String) — Identifier of the backup or restore operation.
  • name (String) — Name of the backup storage (the contents of the FROM or TO clause).
  • status (Enum8) — Operation status. Possible values:
    • 'CREATING_BACKUP'
    • 'BACKUP_CREATED'
    • 'BACKUP_FAILED'
    • 'RESTORING'
    • 'RESTORED'
    • 'RESTORE_FAILED'
  • error (String) — Error message of the failed operation (empty string for successful operations).
  • start_time (DateTime) — Start time of the operation.
  • end_time (DateTime) — End time of the operation.
  • num_files (UInt64) — Number of files stored in the backup.
  • total_size (UInt64) — Total size of files stored in the backup.
  • num_entries (UInt64) — Number of entries in the backup, i.e. the number of files inside the folder if the backup is stored as a folder, or the number of files inside the archive if the backup is stored as an archive. It is not the same as num_files if it's an incremental backup or if it contains empty files or duplicates. The following is always true: num_entries <= num_files.
  • uncompressed_size (UInt64) — Uncompressed size of the backup.
  • compressed_size (UInt64) — Compressed size of the backup. If the backup is not stored as an archive it equals to uncompressed_size.
  • files_read (UInt64) — Number of files read during the restore operation.
  • bytes_read (UInt64) — Total size of files read during the restore operation.

Example

This is essentially the same information that is written in the system table system.backups:

See Also