INSERT имеет больше целевых столбцов, чем выражения с загружаемым объектом JSON

Question

Я пытаюсь запустить простой скрипт вставки, который загрузит объект json в postgresql db. Я получаю следующее сообщение об ошибке:

No data found
ERROR:  INSERT has more target columns than expressions
LINE 132: INSERT INTO books (title, author, genre, year, createdAt, up...
                                                         ^
SQL state: 42601
Character: 4152


CREATE TABLE Books (id SERIAL PRIMARY KEY, title VARCHAR(255) NOT NULL, author VARCHAR(255) NOT NULL, genre VARCHAR(255), year INTEGER, createdAt timestamp with time zone NOT NULL, updatedAt  TIMESTAMP WITH TIME ZONE NOT NULL)

WITH books_json (doc) AS (VALUES(
'[
    {
        "author": "Jane Austen",
        "createdAt": "2018-10-04 18:21:59.011 +00:00",
        "genre": "Classic",
        "title": "Emma",
        "updatedAt": "2018-10-04 18:21:59.011 +00:00",
        "year": 1815
    }
]'::json))
INSERT INTO books (title, author, genre, year, createdAt, updatedAt)
SELECT p.* FROM books_json l CROSS JOIN lateral
json_populate_recordset(NULL::contacts, doc) AS p ON conflict (id)
do UPDATE SET name = excluded.name, active = excluded.active;

Answer 1

Вот как бы я это сделал. Сначала я расширяю массив на строки (в данном случае только одну строку), а затем разыменовываю и преобразую (при необходимости) каждый ключ.

WITH books_json (doc) AS (VALUES(
'[
    {
        "author": "Jane Austen",
        "createdAt": "2018-10-04 18:21:59.011 +00:00",
        "genre": "Classic",
        "title": "Emma",
        "updatedAt": "2018-10-04 18:21:59.011 +00:00",
        "year": 1815
    }
]'::json)
), expand as (
  select json_array_elements(doc) as doc
   from books_json
)
insert into books (title, author, genre, year, createdat, updatedat)
select doc->>'title' as title,
       doc->>'author' as author,
       doc->>'genre' as genre,
       (doc->>'year')::int as year,
       (doc->>'createdAt')::timestamptz as createdat,
       (doc->>'updatedAt')::timestamptz as updatedat
  from expand;