Question

我正在尝试实施PIVOT，但我无法在其中执行基本操作。

当前表：

week_no  username  days      pick_count duration
------------------------------------------------
Week 50  Beck W    Wednesday 227        7978
Week 50  Beck W    Friday    320        7481
Week 50  Beck W    Friday    282        5718
Week 50  Cockram D Thursday  165        10478
Week 50  Cowell P  Thursday  145        14403
Week 50  Cowell P  Thursday  159        7450
Week 50  Cowell P  Friday    217        13101
...

预期结果：

week_no username  monday tuesday wednesday thursday friday saturday sunday
--------------------------------------------------------------------------
Week 50 Beck W    NULL   NULL    102       NULL     164    NULL     NULL
Week 50 Cockram D NULL   NULL    NULL      56       NULL   NULL     NULL
Week 50 Cowell P  NULL   NULL    NULL      50       59     NULL     NULL
...

预期结果应按如下方式计算：pick_count * 3600 / duration。这是我有计算问题的计算。当PIVOT像这样

时

SELECT 
    *
FROM 
(
    SELECT 
        week_no,
        username,
        days,
        pick_count,
        duration
    FROM
        table
) AS src
PIVOT 
(
    SUM(pick_count) * 3600 / SUM(duration) FOR days IN (monday, tuesday, wednesday, thursday, friday, saturday, sunday)
) AS pvt

我得到Incorrect syntax near '*'。

Answer 1

PIVOT不是很灵活。

您可以使用旧式交叉标签方法。

SELECT week_no,
       username,
       SUM(CASE WHEN days = 'monday' then pick_count end) * 3600 
                    / SUM(CASE WHEN days = 'monday' then duration end) as monday,
       SUM(CASE WHEN days = 'tuesday' then pick_count end) * 3600 
                    / SUM(CASE WHEN days = 'tuesday' then duration end) as tuesday
/*TODO: Add other five days*/
FROM   YourTable
GROUP  BY week_no,
          username

Answer 2

我最终找到了我想要的东西。实际上，我需要做的就是在SELECT而不是PIVOT计算计算。

SELECT 
    *
FROM 
(
    SELECT 
        week_no,
        username,
        days,
        SUM(pick_count) * 3600 / SUM(duration) AS pick_rate
    FROM
        table
    GROUP BY
        week_no,
        username,
        days
) AS src
PIVOT 
(
    MAX(pick_rate) FOR days IN (monday, tuesday, wednesday, thursday, friday, saturday, sunday)
) AS pvt

在数据透视表中执行操作

2 个答案: