Ability to use more than two different queries per layer

[t-rex-tileserver]

Ability to use more than two different queries per layer

[pka]

Your example looks right to me, but probably the algorithm is too simplistic.
When choosing the query for a given zoom level, it selects the first query entry with the requested zoom level within minzoom and maxzoom (https://github.com/pka/t-rex/blob/master/src/core/layer.rs#L68).
So if you place the default query at the end, it should work for now.

[pka]

After improving the algorithm to select a zoom dependent query, the behaviour for your example is still not clear between zoom levels 0 to 6. Shouldn't it be:

[[tileset.layer]]
name = "waterareas"
srid = 3857
geometry_field = "geom"
geometry_type = "MULTIPOLYGON"
fid_field = "osm_id"

  [[tileset.layer.query]]
  maxzoom = 6
  sql = """
  SELECT osm_id, ST_Multi(geometry) AS geom
  FROM osm_waterareas_gen0
  WHERE geometry && !bbox!"""

  [[tileset.layer.query]]
  minzoom = 7
  maxzoom = 10
  sql = """
  SELECT osm_id, ST_Multi(geometry) AS geom
  FROM osm_waterareas_gen1
  WHERE geometry && !bbox!"""

  [[tileset.layer.query]]
  minzoom = 11
  sql = """
  SELECT osm_id, ST_Multi(geometry) AS geom
  FROM osm_waterareas
  WHERE geometry && !bbox!"""