Versions:
ALTER TABLE (Compression) communityCommunity functions are available under Timescale Community Edition. Click to learn more.
community
Community functions are available under Timescale Community Edition. Click to learn more.
'ALTER TABLE' statement is used to turn on compression and set compression options.
The syntax is:
ALTER TABLE <table_name> SET (timescaledb.compress, timescaledb.compress_orderby = '<column_name> [ASC | DESC] [ NULLS { FIRST | LAST } ] [, ...]',
timescaledb.compress_segmentby = '<column_name> [, ...]'
);Required arguments
| Name | Type | Description |
|---|---|---|
timescaledb.compress | BOOLEAN | Enable/Disable compression |
Optional arguments
| Name | Type | Description |
|---|---|---|
timescaledb.compress_orderby | TEXT | Order used by compression, specified in the same way as the ORDER BY clause in a SELECT query. The default is the descending order of the hypertable's time column. |
timescaledb.compress_segmentby | TEXT | Column list on which to key the compressed segments. An identifier representing the source of the data such as device_id or tags_id is usually a good candidate. The default is no segment by columns. |
Parameters
| Name | Type | Description |
|---|---|---|
table_name | TEXT | Hypertable that supports compression |
column_name | TEXT | Column used to order by and/or segment by |
Sample usage
Configure a hypertable that ingests device data to use compression.
ALTER TABLE metrics SET (timescaledb.compress, timescaledb.compress_orderby = 'time DESC', timescaledb.compress_segmentby = 'device_id');Found an issue on this page?
Report an issue!