system.zookeeper_watches

Description

Shows currently active watches registered by this ClickHouse server on ZooKeeper nodes (including auxiliary ZooKeepers). Each row represents one watch.

Columns

• zookeeper_name (String) — Name of the ZooKeeper connection (default for the main connection, or the auxiliary name).
• create_time (DateTime) — Time when the watch was created.
• create_time_microseconds (DateTime64) — Time when the watch was created with microsecond precision.
• path (String) — ZooKeeper path being watched.
• session_id (Int64) — Session ID of the connection that registered the watch.
• request_xid (Int64) — XID of the request that created the watch.
• op_num (Enum) — The type of the request that created the watch.
• watch_type (Enum8) — Watch type. Possible values:
  • Children — watching for changes in the list of child nodes (set by List operations).
  • Exists — watching for node creation or deletion.
  • Data — watching for changes in node data (set by Get operations).

Example:

SELECT * FROM system.zookeeper_watches FORMAT Vertical;

Row 1:
──────
zookeeper_name:           default
create_time:              2026-03-16 12:00:00
create_time_microseconds: 2026-03-16 12:00:00.123456
path:                     /clickhouse/task_queue/ddl
session_id:               106662742089334927
request_xid:              10858
op_num:                   List
watch_type:               Children

See Also

• ZooKeeper
• ZooKeeper guide