TimescaleDB API Reference - move_chunk() Community - 《TimescaleDB v2.1 Documentation》

move_chunk() Community

move_chunk() Community

TimescaleDB allows users to move data (and indexes) to alternative tablespaces. This allows the user the ability to move data to more cost effective storage as it ages. This function acts like the combination of the PostgreSQL CLUSTER command and the PostgreSQL ALTER TABLE…SET TABLESPACE command.

Unlike these PostgreSQL commands, however, the move_chunk function employs lower lock levels so that the chunk and hypertable are able to be read for most of the process. This comes at a cost of slightly higher disk usage during the operation. For a more detailed discussion of this capability, please see the Data Tiering documentation.

Required Arguments

Name	Description
`chunk`	(REGCLASS) Name of chunk to be moved.
`destination_tablespace`	(Name) Target tablespace for chunk you are moving.
`index_destination_tablespace`	(Name) Target tablespace for index associated with the chunk you are moving.

Optional Arguments

Name	Description
`reorder_index`	(REGCLASS) The name of the index (on either the hypertable or chunk) to order by.
`verbose`	(BOOLEAN) Setting to true will display messages about the progress of the move_chunk command. Defaults to false.

Sample Usage

SELECT move_chunk(
  chunk => '_timescaledb_internal._hyper_1_4_chunk',
  destination_tablespace => 'tablespace_2',
  index_destination_tablespace => 'tablespace_3',
  reorder_index => 'conditions_device_id_time_idx',
  verbose => TRUE
);