set_chunk_time_interval()

Sets the chunk_time_interval on a hypertable. The new interval is used when new chunks are created, and time intervals on existing chunks are not changed.

For a TIMESTAMP column, set chunk_time_interval to 24 hours:

SELECT set_chunk_time_interval('conditions', INTERVAL '24 hours');
SELECT set_chunk_time_interval('conditions', 86400000000);

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For a time column expressed as the number of milliseconds since the UNIX epoch, set chunk_time_interval to 24 hours:

SELECT set_chunk_time_interval('conditions', 86400000);

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If you change chunk time interval you may see a chunk that is smaller than the new interval. For example, if you have two 7-day chunks that cover 14 days, then change chunk_time_interval to 3 days, you may end up with a transition chunk covering one day. This happens because the start and end of the new chunk is calculated based on dividing the timeline by the chunk_time_interval starting at epoch 0. This leads to the following chunks [0, 3), [3, 6), [6, 9), [9, 12), [12, 15), [15, 18) and so on. The two 7-day chunks covered data up to day 14: [0, 7), [8, 14), so the 3-day chunk for [12, 15) is reduced to a one day chunk. The following chunk [15, 18) is created as a full 3 day chunk.

The valid types for the chunk_time_interval depend on the type used for the hypertable time column:

For more information, see hypertable partitioning.