timescaledb_information.data_nodes
- Available columns
- Sample usage
timescaledb_information.hypertables
- Available columns
- Sample usage

timescaledb_information.data_nodes

Get information on data nodes. This function is specific to running TimescaleDB in a multi-node setup.

Available columns

Name	Type	Description
`node_name`	TEXT	Data node name.
`owner`	REGCLASS	Oid of the user, who added the data node.
`options`	JSONB	Options used when creating the data node.

Sample usage

Get metadata related to data nodes.


SELECT * FROM timescaledb_information.data_nodes;
 node_name    | owner      | options                        
--------------+------------+--------------------------------
 dn1         | postgres   | {host=localhost,port=15431,dbname=test}   
 dn2         | postgres   | {host=localhost,port=15432,dbname=test} 
(2 rows)

timescaledb_information.hypertables

Get metadata information about hypertables.

Available columns

Name	Type	Description
`hypertable_schema`	TEXT	Schema name of the hypertable
`hypertable_name`	TEXT	Table name of the hypertable
`owner`	TEXT	Owner of the hypertable
`num_dimensions`	SMALLINT	Number of dimensions
`num_chunks`	BIGINT	Number of chunks
`compression_enabled`	BOOLEAN	Is compression enabled on the hypertable?
`is_distributed`	BOOLEAN	Is the hypertable distributed?
`replication_factor`	SMALLINT	Replication factor for a distributed hypertable
`data_nodes`	ARRAY	Nodes on which hypertable is distributed
`tablespaces`	ARRAY	Tablespaces attached to the hypertable

Sample usage

Get information about a hypertable.


CREATE TABLE dist_table(time timestamptz, device int, temp float);
SELECT create_distributed_hypertable('dist_table', 'time', 'device', replication_factor => 2);
SELECT * FROM timescaledb_information.hypertables
  WHERE hypertable_name = 'dist_table';
-[ RECORD 1 ]-------+-----------
hypertable_schema   | public
hypertable_name     | dist_table
owner               | postgres 
num_dimensions      | 2
num_chunks          | 3
compression_enabled | f
is_distributed      | t
replication_factor  | 2
data_nodes          | {node_1, node_2}
tablespaces         |