lttb()

Toolkit

TimescaleDB Toolkit functions are available under Timescale Community Edition. They are automatically included with Timescale Cloud. Click to learn more.

Experimental

Experimental features are not suitable for production environments. They are included under the TimescaleDB experimental schema. Click to learn more.

Largest Triangle Three Buckets is a downsampling method that tries to retain visual similarity between the downsampled data and the original dataset. The TimescaleDB Toolkit implementation of this takes (timestamp, value) pairs, sorts them if needed, and downsamples them.

Required arguments

Returns

Sample usage

This example creates a dramatically downsampled data set from a sample_data table:

SELECT time, value
FROM toolkit_experimental.unnest((
    SELECT toolkit_experimental.lttb(time, val, 4)
    FROM sample_data))

The output for this query:

time          |       value
------------------------+--------------------
 2020-01-11 00:00:00+00 |   12.7015115293407
 2020-02-01 00:00:00+00 |  5.004324248633603
 2020-03-03 00:00:00+00 | 14.982710485116087
 2020-04-20 00:00:00+00 | 10.022128489940254