--- slug: /en/operations/system-tables/backup_log --- # backup_log Contains logging entries with the information about `BACKUP` and `RESTORE` operations. Columns: - `hostname` ([LowCardinality(String)](../../sql-reference/data-types/string.md)) — Hostname of the server executing the query. - `event_date` ([Date](../../sql-reference/data-types/date.md)) — Date of the entry. - `event_time_microseconds` ([DateTime64](../../sql-reference/data-types/datetime64.md)) — Time of the entry with microseconds precision. - `id` ([String](../../sql-reference/data-types/string.md)) — Identifier of the backup or restore operation. - `name` ([String](../../sql-reference/data-types/string.md)) — Name of the backup storage (the contents of the `FROM` or `TO` clause). - `status` ([Enum8](../../sql-reference/data-types/enum.md)) — Operation status. Possible values: - `'CREATING_BACKUP'` - `'BACKUP_CREATED'` - `'BACKUP_FAILED'` - `'RESTORING'` - `'RESTORED'` - `'RESTORE_FAILED'` - `error` ([String](../../sql-reference/data-types/string.md)) — Error message of the failed operation (empty string for successful operations). - `start_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — Start time of the operation. - `end_time` ([DateTime](../../sql-reference/data-types/datetime.md)) — End time of the operation. - `num_files` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Number of files stored in the backup. - `total_size` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Total size of files stored in the backup. - `num_entries` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — 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](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Uncompressed size of the backup. - `compressed_size` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Compressed size of the backup. If the backup is not stored as an archive it equals to `uncompressed_size`. - `files_read` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Number of files read during the restore operation. - `bytes_read` ([UInt64](../../sql-reference/data-types/int-uint.md#uint-ranges)) — Total size of files read during the restore operation. **Example** ```sql BACKUP TABLE test_db.my_table TO Disk('backups_disk', '1.zip') ``` ```response ┌─id───────────────────────────────────┬─status─────────┐ │ e5b74ecb-f6f1-426a-80be-872f90043885 │ BACKUP_CREATED │ └──────────────────────────────────────┴────────────────┘ ``` ```sql SELECT * FROM system.backup_log WHERE id = 'e5b74ecb-f6f1-426a-80be-872f90043885' ORDER BY event_date, event_time_microseconds \G ``` ```response Row 1: ────── hostname: clickhouse.eu-central1.internal event_date: 2023-08-19 event_time_microseconds: 2023-08-19 11:05:21.998566 id: e5b74ecb-f6f1-426a-80be-872f90043885 name: Disk('backups_disk', '1.zip') status: CREATING_BACKUP error: start_time: 2023-08-19 11:05:21 end_time: 1970-01-01 03:00:00 num_files: 0 total_size: 0 num_entries: 0 uncompressed_size: 0 compressed_size: 0 files_read: 0 bytes_read: 0 Row 2: ────── hostname: clickhouse.eu-central1.internal event_date: 2023-08-19 event_time_microseconds: 2023-08-19 11:08:56.916192 id: e5b74ecb-f6f1-426a-80be-872f90043885 name: Disk('backups_disk', '1.zip') status: BACKUP_CREATED error: start_time: 2023-08-19 11:05:21 end_time: 2023-08-19 11:08:56 num_files: 57 total_size: 4290364870 num_entries: 46 uncompressed_size: 4290362365 compressed_size: 3525068304 files_read: 0 bytes_read: 0 ``` ```sql RESTORE TABLE test_db.my_table FROM Disk('backups_disk', '1.zip') ``` ```response ┌─id───────────────────────────────────┬─status───┐ │ cdf1f731-52ef-42da-bc65-2e1bfcd4ce90 │ RESTORED │ └──────────────────────────────────────┴──────────┘ ``` ```sql SELECT * FROM system.backup_log WHERE id = 'cdf1f731-52ef-42da-bc65-2e1bfcd4ce90' ORDER BY event_date, event_time_microseconds \G ``` ```response Row 1: ────── hostname: clickhouse.eu-central1.internal event_date: 2023-08-19 event_time_microseconds: 2023-08-19 11:09:19.718077 id: cdf1f731-52ef-42da-bc65-2e1bfcd4ce90 name: Disk('backups_disk', '1.zip') status: RESTORING error: start_time: 2023-08-19 11:09:19 end_time: 1970-01-01 03:00:00 num_files: 0 total_size: 0 num_entries: 0 uncompressed_size: 0 compressed_size: 0 files_read: 0 bytes_read: 0 Row 2: ────── hostname: clickhouse.eu-central1.internal event_date: 2023-08-19 event_time_microseconds: 2023-08-19 11:09:29.334234 id: cdf1f731-52ef-42da-bc65-2e1bfcd4ce90 name: Disk('backups_disk', '1.zip') status: RESTORED error: start_time: 2023-08-19 11:09:19 end_time: 2023-08-19 11:09:29 num_files: 57 total_size: 4290364870 num_entries: 46 uncompressed_size: 4290362365 compressed_size: 4290362365 files_read: 57 bytes_read: 4290364870 ``` This is essentially the same information that is written in the system table `system.backups`: ```sql SELECT * FROM system.backups ORDER BY start_time ``` ```response ┌─id───────────────────────────────────┬─name──────────────────────────┬─status─────────┬─error─┬──────────start_time─┬────────────end_time─┬─num_files─┬─total_size─┬─num_entries─┬─uncompressed_size─┬─compressed_size─┬─files_read─┬─bytes_read─┐ │ e5b74ecb-f6f1-426a-80be-872f90043885 │ Disk('backups_disk', '1.zip') │ BACKUP_CREATED │ │ 2023-08-19 11:05:21 │ 2023-08-19 11:08:56 │ 57 │ 4290364870 │ 46 │ 4290362365 │ 3525068304 │ 0 │ 0 │ │ cdf1f731-52ef-42da-bc65-2e1bfcd4ce90 │ Disk('backups_disk', '1.zip') │ RESTORED │ │ 2023-08-19 11:09:19 │ 2023-08-19 11:09:29 │ 57 │ 4290364870 │ 46 │ 4290362365 │ 4290362365 │ 57 │ 4290364870 │ └──────────────────────────────────────┴───────────────────────────────┴────────────────┴───────┴─────────────────────┴─────────────────────┴───────────┴────────────┴─────────────┴───────────────────┴─────────────────┴────────────┴────────────┘ ``` **See Also** - [Backup and Restore](../../operations/backup.md)