mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-14 10:22:10 +00:00
13d9a4eebe
Edit page link is fixed too for both language versions of documentation.
2.2 KiB
2.2 KiB
system.zookeeper
Allows reading data from the ZooKeeper cluster defined in the config. The query must have a 'path' equality condition in the WHERE clause. This is the path in ZooKeeper for the children that you want to get data for.
The query SELECT * FROM system.zookeeper WHERE path = '/clickhouse'
outputs data for all children on the /clickhouse
node.
To output data for all root nodes, write path = '/'.
If the path specified in 'path' doesn't exist, an exception will be thrown.
Columns:
name String - Name of the node.
path String - Path to the node.
value String - Value of the node.
dataLength Int32 - Size of the value.
numChildren Int32 - Number of children.
czxid Int64 - ID of the transaction that created the node.
mzxid Int64 - ID of the transaction that last changed the node.
pzxid Int64 - ID of the transaction that last added or removed children.
ctime DateTime - Time of node creation.
mtime DateTime - Time of the last node modification.
version Int32 - Node version - the number of times the node was changed.
cversion Int32 - Number of added or removed children.
aversion Int32 - Number of changes to ACL.
ephemeralOwner Int64 - For ephemeral nodes, the ID of the session that owns this node.
Example:
SELECT *
FROM system.zookeeper
WHERE path = '/clickhouse/tables/01-08/visits/replicas'
FORMAT Vertical
Row 1:
──────
name: example01-08-1.yandex.ru
value:
czxid: 932998691229
mzxid: 932998691229
ctime: 2015-03-27 16:49:51
mtime: 2015-03-27 16:49:51
version: 0
cversion: 47
aversion: 0
ephemeralOwner: 0
dataLength: 0
numChildren: 7
pzxid: 987021031383
path: /clickhouse/tables/01-08/visits/replicas
Row 2:
──────
name: example01-08-2.yandex.ru
value:
czxid: 933002738135
mzxid: 933002738135
ctime: 2015-03-27 16:57:01
mtime: 2015-03-27 16:57:01
version: 0
cversion: 37
aversion: 0
ephemeralOwner: 0
dataLength: 0
numChildren: 7
pzxid: 987021252247
path: /clickhouse/tables/01-08/visits/replicas