Postgres 16

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create table my_table(jdata) as values
  ('{"apple": 13.1, "banana": 2.0, "zucchini": 7.2, "orange": 19.1}'::json);

SELECT 1

select jdata from my_table;

jdata

{"apple": 13.1, "banana": 2.0, "zucchini": 7.2, "orange": 19.1}

SELECT 1

select jdata::jsonb from my_table; --jsonb reorders the keys

jdata

{"apple": 13.1, "banana": 2.0, "orange": 19.1, "zucchini": 7.2}

SELECT 1

select json_object_agg(k,v order by v::numeric)
from my_table
cross join json_each_text(jdata) as j(k,v)
group by my_table.ctid;

json_object_agg

{ "banana" : "2.0", "zucchini" : "7.2", "apple" : "13.1", "orange" : "19.1" }

SELECT 1

insert into my_table values 
  ('{"apple": "abc13.1def", "banana": "abc2.0def", "zucchini": "abc7.2def", "orange": "abc19.1def"}'::json);

INSERT 0 1

select json_object_agg(k,v order by v)
from my_table
cross join json_each_text(jdata) as j(k,v)
group by my_table.ctid;

json_object_agg

{ "apple" : "13.1", "orange" : "19.1", "banana" : "2.0", "zucchini" : "7.2" }

{ "apple" : "abc13.1def", "orange" : "abc19.1def", "banana" : "abc2.0def", "zucchini" : "abc7.2def" }

SELECT 2

CREATE COLLATION num_ignore_punct (
  provider = icu, 
  deterministic = false, 
  locale = 'und-u-ka-shifted-kn');

select json_object_agg(k,v order by v collate num_ignore_punct)
from my_table
cross join json_each_text(jdata) as j(k,v)
group by my_table.ctid;

CREATE COLLATION

json_object_agg

{ "banana" : "2.0", "zucchini" : "7.2", "apple" : "13.1", "orange" : "19.1" }

{ "banana" : "abc2.0def", "zucchini" : "abc7.2def", "apple" : "abc13.1def", "orange" : "abc19.1def" }

SELECT 2