Is there a reason placex.extratags keys are sorted by length?

[mtmail]

Is this unintended behavior, side effect of a default or does Nominatim or osm2psql set it somewhere explicitly during import? I checked the settings/*.lua script but can't see sorting.

(jsbonb_pretty, hstore_to_jsonb don't influence the sorting)

SELECT
    jsonb_pretty(hstore_to_jsonb(extratags))
FROM
    placex
WHERE
    osm_type = 'R'
    AND osm_id = 347950;
                                    jsonb_pretty
-------------------------------------------------------------------------------------
 {                                                                                  +
     "ele": "13",                                                                   +
     "place": "city",                                                               +
     "capital": "4",                                                                +
     "ref:ine": "08019000000",                                                      +
     "wikidata": "Q1492",                                                           +
     "idee:name": "Barcelona",                                                      +
     "wikipedia": "ca:Barcelona",                                                   +
     "population": "1636193",                                                       +
     "source:ele": "MDT5",                                                          +
     "source:date": "2011-06",                                                      +
     "source:name": "Nomenclátor Geográfico de Municipios y Entidades de Población",+
     "linked_place": "city",                                                        +
     "ine:municipio": "08019",                                                      +
     "source:name:br": "same as name",                                              +
     "source:name:oc": "Lo Congrès",                                                +
     "population:date": "2022"                                                      +
 }

[lonvia]

I presume that this is a side-effect of how hstore is stored internally by PostgreSQL. You see the same with the name field. It is certainly not intentional. You should not make any assumption about the order of these fields in the response.