system.database_replicas

System table containing information about and status of replicated database.

Description

Contains information of each Replicated database replicas.

Columns

• database (String) — The name of the Replicated database is in.
• is_readonly (UInt8) — Whether the database replica is in read-only mode.
• max_log_ptr (Int32) — Maximum entry number in the log of general activity.
• replica_name (String) — Replica name in ClickHouse Keeper.
• replica_path (String) — Path to replica data in ClickHouse Keeper.
• zookeeper_path (String) — Path to database data in ClickHouse Keeper.
• shard_name (String) — The name of the shard in the cluster.
• log_ptr (Int32) — Maximum entry number in the log of general activity that the replica copied to its execution queue, plus one.
• total_replicas (UInt32) — The total number of known replicas of this database.
• zookeeper_exception (String) — The last exception message, got if the error happened when fetching the info from ClickHouse Keeper.
• is_session_expired (UInt8) — The session with ClickHouse Keeper has expired. Basically the same as is_readonly.

Example

SELECT * FROM system.database_replicas FORMAT Vertical;

Row 1:
──────
database:            db_2
is_readonly:         0
max_log_ptr:         2
replica_name:        replica1
replica_path:        /test/db_2/replicas/shard1|replica1
zookeeper_path:      /test/db_2
shard_name:          shard1
log_ptr:             2
total_replicas:      1
zookeeper_exception: 
is_session_expired:  0