子查询的两个日期之间的差异

Question

我正试图计算Postgres上两个日期之间的差异。首先我得到日期：

SELECT * FROM
(
    SELECT 
            to_char(to_timestamp(t.time/1000000), 'DD/MM/YYYY HH24:MI:SS') AS initial_date
    FROM
            book.ticket AS t

    WHERE status = 'planning'
) AS initial_date,

(
    SELECT 
            to_char(to_timestamp(t.time/1000000), 'DD/MM/YYYY HH24:MI:SS') AS final_date
    FROM
            book.ticket AS t

    WHERE status = 'closed'
) AS final_date

然后我想做类似的事情来计算之前恢复日期之间的差异：

SELECT DATE_PART('day', final_date::timestamp - initial_date::timestamp)

但我不知道如何将这个最后一部分（那个计算的部分）和其他查询放在一起。有人能帮我吗？

Answer 1

好的，伙计们！经过所有这些讨论，我解决了我的问题。我将发布下面的代码。感谢您的帮助，每个人的意见都很重要！

SELECT t1.id, t1.initial_date, t2.id, t2.final_date, t2.final_date - t1.initial_date as dif
FROM (

        (
        SELECT 
            t.id,
            to_timestamp(t.time/1000000) AS initial_date
        FROM
            book.ticket AS t
        WHERE status = 'planning' 
        )  t1

JOIN   (
        SELECT 
            t.id,
            to_timestamp(t.time/1000000) AS final_date
        FROM
            book.ticket AS t
        WHERE status = 'closed'  
       )  t2
ON t1.id  = t2.id 
)