Manually drop chunks

Drop chunks manually by time value. For example, drop chunks containing data older than 30 days.

Note

Dropping chunks manually is a one-time operation. To automatically drop chunks as they age, set up a data retention policy.

Drop chunks older than a certain date

To drop chunks older than a certain date, use the drop_chunks function. Provide the name of the hypertable to drop chunks from, and a time interval beyond which to drop chunks.

For example, to drop chunks with data older than 24 hours:

SELECT drop_chunks('conditions', INTERVAL '24 hours');

Drop chunks between 2 dates

You can also drop chunks between 2 dates. For example, drop chunks with data between 3 and 4 months old.

Supply a second INTERVAL argument for the newer_than cutoff:

SELECT drop_chunks(
  'conditions',
  older_than => INTERVAL '3 months',
  newer_than => INTERVAL '4 months'
)

Drop chunks in the future

You can also drop chunks in the future, for example, to correct data with the wrong timestamp. To drop all chunks that are more than 3 months in the future, from a hypertable called conditions:

SELECT drop_chunks(
  'conditions',
  newer_than => now() + INTERVAL '3 months'
);

Learn more

• Create a data retention policy: Automate chunk deletion based on age.
• Understand chunks: How chunks work and why they matter.
• drop_chunks() reference: Full API reference with all parameters.
• show_chunks() reference: List chunks before dropping them.