Wrong indexes at distributed hypertable for iot case

[Dmitry Sysolyatin]

Hi!
There is a point in the documentation for tsdb_load_timescale:

Please note, -in-table-partition-tag is required for multi-node TimescaleDB benchmark testing. Currently, the multi-node query engine does not support push-down of JOINs and so the most efficient queries will filter on the primary tag name.

If specify -in-table-partition-tag flag then index (name, time) will be created instead of (tags_id, time). But benchmark has queries which look like:

SELECT t.%s, t.%s, r.*
FROM tags t INNER JOIN LATERAL
	(SELECT longitude, latitude
	FROM readings r
	WHERE r.tags_id=t.id
	ORDER BY time DESC LIMIT 1)  r ON true
WHERE t.%s`

It is superslow because readings does not have (tags_id, time) index