SELECT row_to_json main_json_query FROM SELECT SELECT coalesce array_a

SELECT row_to_json(main_json_query.*)
FROM (
    SELECT (
        SELECT coalesce(
            array_agg(data_query.data),
            CAST(ARRAY[] AS JSON[])
        ) AS data
        FROM (
            SELECT
                json_build_object(
                    'id',
                    CAST(article.id AS VARCHAR),
                    'type',
                    'articles',
                    'attributes',
                    json_build_object(
                        'name',
                        article.name
                    ),
                    'relationships',
                    json_build_object(
                        'comments',
                        json_build_object(
                            'data',
                            (
                                SELECT
                                coalesce(
                                    array_agg(relationships.json_object),
                                    CAST(ARRAY[] AS JSON[])
                                ) AS coalesce_2
                                FROM (
                                    SELECT json_build_object(
                                        'id',
                                        CAST(comment.id AS VARCHAR),
                                        'type',
                                        'comments'
                                    ) AS json_object
                                    FROM comment
                                    WHERE article.id = comment.article_id
                                ) AS relationships
                            )
                        )
                    )
                ) AS data
            FROM article
        ) AS data_query
    ) AS data
) AS main_json_query