Time-weighted rollup: called Result::unwrap() on an Err value: OrderError

[michael-sayapin]

Relevant system information:

• OS: Ubuntu 22.04
• PostgreSQL version (output of SELECT version();): PostgreSQL 14.15 (Ubuntu 14.15-1.pgdg22.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0, 64-bit
• TimescaleDB Toolkit version (output of \dx timescaledb_toolkit in psql): 1.19.0
• Installation method: Docker timescale/timescaledb-ha:pg14-ts2.17

Describe the bug

Time-weighted average rollup cannot rollup disjointed data.

# SELECT time_bucket('9999y', t), rollup(tw_column) FROM my_cagg GROUP BY 1;
ERROR:  called `Result::unwrap()` on an `Err` value: OrderError

I tried:

• adding a CTE or subquery to filter tw_column IS NOT NULL
• ordering by t in CTE / subquery

The issue can be reproduced when I have two records like this:

        t               |                                                                                 tw_column
------------------------+----------------------------------------------------------------------------------------------------
 2025-01-14 01:00:00+00 | (version:1,first:(ts:"2025-01-14 01:00:24+00",val:1),last:(ts:"2025-01-14 01:59:25+00",val:2),weighted_sum:5,method:Linear)
 2025-01-14 01:00:00+00 | (version:1,first:(ts:"2025-01-14 01:00:25+00",val:3),last:(ts:"2025-01-14 01:59:25+00",val:4),weighted_sum:7,method:Linear)

Expected behavior

Merging of two time-weighted aggregates.