system.disks
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 information about disks defined in the server configuration.
Columns:
name
(String) — Name of a disk in the server configuration.path
(String) — Path to the mount point in the file system.free_space
(UInt64) — Free space on disk in bytes.total_space
(UInt64) — Disk volume in bytes.unreserved_space
(UInt64) — Free space which is not taken by reservations (free_space minus the size of reservations taken by merges, inserts, and other disk write operations currently running).keep_free_space
(UInt64) — Amount of disk space that should stay free on disk in bytes. Defined in the keep_free_space_bytes parameter of disk configuration.type
(String) — The disk type which tells where this disk stores the data - RAM, local drive or remote storage.object_storage_type
(String) — Type of object storage if disk type is object_storagemetadata_type
(String) — Type of metadata storage if disk type is object_storageis_encrypted
(UInt8) — Flag which shows whether this disk ecrypts the underlying data.is_read_only
(UInt8) — Flag which indicates that you can only perform read operations with this disk.is_write_once
(UInt8) — Flag which indicates if disk is write-once. Which means that it does support BACKUP to this disk, but does not support INSERT into MergeTree table on this disk.is_remote
(UInt8) — Flag which indicated what operations with this disk involve network interaction.is_broken
(UInt8) — Flag which indicates if disk is broken. Broken disks will have 0 space and cannot be used.cache_path
(String) — The path to the cache directory on local drive in case when the disk supports caching.
Example