Как отсортировать файл json в таблице postgres?

Question

У меня есть json-файл, который мне нужно разделить на части и отсортировать каждую часть в его колонке.

это мой стол:

create table json_data(
row_id int, 
id varchar PRIMARY KEY, 
created_at timestamp , 
closed_at timestamp , 
open boolean, 
num_changes int, 
user_name varchar, 
uid int, 
min_lat real, 
max_lat real, 
min_lon real, 
max_lon real, 
created_by varchar, 
imagery_used varchar, 
version varchar, 
comment varchar 
); 

и это мой пример Json файл:

{"id":"19739143","created_at":"2013-12-31T22:28:28Z","closed_at":"2013-12-31T23:59:11Z","open":"false","num_changes":"81","user":"47NOE","uid":"1811738","min_lat":"18.0813259","max_lat":"18.1163397","min_lon":"-63.0392394","max_lon":"-63.0205645","created_by":"Potlatch 2","build":"2.3-605-gbec0ea7","version":"2.3"} 
{"id":"19739670","created_at":"2013-12-31T23:59:13Z","closed_at":"2013-12-31T23:59:15Z","open":"false","num_changes":"17","user":"mituc","uid":"1860759","min_lat":"37.0432953","max_lat":"37.0619236","min_lon":"-76.3896156","max_lon":"-76.3625439","created_by":"iD 1.3.4","imagery_used":"Bing"} 

Я попытался следующий код, но если одна из частей не хватает (например, «открытое :»для базы подписки), то все данные просто проведите пальцем влево и показывает неправильный ответ:

SELECT trim('{id:' from split_part(data, ',', 1)) AS id 
     ,trim('created_at:' from split_part(data, ',', 2)) AS created_at 
     ,trim('closed_at:' from split_part(data, ',', 3)) AS closed_at 
     ,trim('open:' from split_part(data, ',', 4))AS open 
     ,trim('num_changes:' from split_part(data, ',', 5)) AS num_changes 
     ,trim('user:' from split_part(data, ',', 6)) AS user_name 
     ,trim('uid:' from split_part(data, ',', 7)) AS uid 
     ,trim('min_lat:' from split_part(data, ',', 8)) AS min_lat 
     ,trim('max_lat:' from split_part(data, ',', 9)) AS max_lat 
     ,trim('min_lon:' from split_part(data, ',', 10)) AS min_lon 
     ,trim('max_lon:' from split_part(data, ',', 11)) AS max_lon 
     ,trim('created_by:' from split_part(data, ',', 12)) AS col12 
     ,trim('build:' from split_part(data, ',', 13)) AS col13 
     ,trim('comment:' from split_part(data, ',', 13)) AS col13 
     ,trim('imagery_used:' from split_part(data, ',', 13)) AS col13 
     ,trim('}' from trim('version:' from split_part(data, ',', 14))) AS col14 
FROM json_data_raw; 

или

SELECT trim('{id:' from split_part(data, ',', 1)) AS id 
     ,trim('created_at:' from split_part(data, ',', 2)) AS created_at 

,case 
when substring(split_part(data, ',', 3) from 1 for 10) = 'closed_at:' 
then trim('closed_at:' from split_part(data, ',', 3)) 
when substring(split_part(data, ',', 4) from 1 for 10) = 'closed_at:' 
then trim('closed_at:' from split_part(data, ',', 3)) 
when substring(split_part(data, ',', 5) from 1 for 10) = 'closed_at:' 
then trim('closed_at:' from split_part(data, ',', 3)) 
else null 
end 
AS closed_at 
,case 
when substring(split_part(data, ',', 4) from 1 for 5) = 'open:' 
then trim('open:' from split_part(data, ',', 4)) 
else null 
end 
AS open 
,case 
when substring(split_part(data, ',', 5) from 1 for 12) = 'num_changes:' 
then trim('num_changes:' from split_part(data, ',', 5)) 
else null 
end 
AS num_changes 
,case 
when substring(split_part(data, ',', 6) from 1 for 4) = 'user:' 
then trim('user:' from split_part(data, ',', 6)) 
else null 
end 
AS user 
,case 
when substring(split_part(data, ',', 7) from 1 for 4) = 'uid:' 
then trim('uid:' from split_part(data, ',', 7)) 
else null 
end 
AS uid 
,case 
when substring(split_part(data, ',', 8) from 1 for 8) = 'min_lat:' 
then trim('min_lat:' from split_part(data, ',', 8)) 
else null 
end 
AS min_lat 
,case 
when substring(split_part(data, ',', 9) from 1 for 8) = 'max_lat:' 
then trim('max_lat:' from split_part(data, ',', 9)) 
else null 
end 
AS max_lat 
,case 
when substring(split_part(data, ',', 10) from 1 for 8) = 'min_lon:' 
then trim('min_lon:' from split_part(data, ',', 10)) 
else null 
end 
AS min_lon 
,case 
when substring(split_part(data, ',', 11) from 1 for 8) = 'max_lon:' 
then trim('min_lon:' from split_part(data, ',', 11)) 
else null 
end 
AS max_lon 
,case 
when substring(split_part(data, ',', 12) from 1 for 11) = 'created_by:' 
then trim('created_by:' from split_part(data, ',', 12)) 
else null 
end 
AS created_by 
,case 
when substring(split_part(data, ',', 13) from 1 for 6) = 'build:' 
then trim('build:' from split_part(data, ',', 13)) 
else null 
end 
AS build 
,case 
when substring(split_part(data, ',', 14) from 1 for 8) = 'version:' 
then trim('version:' from split_part(data, ',', 14)) 
else null 
end 
AS version_n 
FROM json_data_raw; 

Как я могу сортировать его так, чтобы каждая деталь была сортировкой до нужной колонки.

Answer 1

Похоже, что вы разбираете JSON с помощью строковых функций манипуляции, таких как split_part. Но Postgres имеет native JSON support. Вы можете преобразовать строку в JSON с ::json. Вы можете запросить объект JSON, например ->>'id'. Например:

select data::json->>'id' as id 
,  data::json->>'created_at' as created_at 
from json_data_raw 

Example at SQL Fiddle.