SQL-Server Unpivot/Pivot Example

Question

Я делаю заявку на управление бронированием гостиниц, и мне нужно показать скорость обучения в месяц в год. Я сделал запрос, который разрешает проблему, но я хочу представить ее в другом формате.

Мой текущий запрос возвращает следующую таблицу (2x12):

January|February|March|April| ..... and so on 
    20  15  18  20 ..... and so on 

И я хочу что-то вроде этого (12x2):

January|20 
February|15 
March|18 
... |... 

Это мой запрос:

Select 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'January' or datename(month, [CheckOut]) = 'January' THEN 1 ELSE 0 END) January, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'February' or datename(month, [CheckOut]) = 'February' THEN 1 ELSE 0 END) February, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'March' or datename(month, [CheckOut]) = 'March' THEN 1 ELSE 0 END) March, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'April' or datename(month, [CheckOut]) = 'April' THEN 1 ELSE 0 END) April, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'May' or datename(month, [CheckOut]) = 'May' THEN 1 ELSE 0 END) May, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'June' or datename(month, [CheckOut]) = 'June' THEN 1 ELSE 0 END) June, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'July' or datename(month, [CheckOut]) = 'July' THEN 1 ELSE 0 END) July, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'August' or datename(month, [CheckOut]) = 'August' THEN 1 ELSE 0 END) August, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'September' or datename(month, [CheckOut]) = 'September' THEN 1 ELSE 0 END) September, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'October' or datename(month, [CheckOut]) = 'October' THEN 1 ELSE 0 END) October, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'November' or datename(month, [CheckOut]) = 'November' THEN 1 ELSE 0 END) November, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'December' or datename(month, [CheckOut]) = 'December' THEN 1 ELSE 0 END) December 
FROM {Booking} INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id] 
WHERE {Booking}.[CheckIn] >= @BeginDate AND {Booking}.[CheckOut] <= @EndDate AND {Status}.[Label] <> 'Canceled' 

Любая помощь будет оценена, я застрял, и theres не так много информации в Интернете, спасибо!

Answer 1

Похоже, что вы пытаетесь сделать UNPIVOT:

SELECT Month, CheckIns 
FROM 
    (Select 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'January' or datename(month, [CheckOut]) = 'January' THEN 1 ELSE 0 END) January, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'February' or datename(month, [CheckOut]) = 'February' THEN 1 ELSE 0 END) February, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'March' or datename(month, [CheckOut]) = 'March' THEN 1 ELSE 0 END) March, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'April' or datename(month, [CheckOut]) = 'April' THEN 1 ELSE 0 END) April, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'May' or datename(month, [CheckOut]) = 'May' THEN 1 ELSE 0 END) May, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'June' or datename(month, [CheckOut]) = 'June' THEN 1 ELSE 0 END) June, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'July' or datename(month, [CheckOut]) = 'July' THEN 1 ELSE 0 END) July, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'August' or datename(month, [CheckOut]) = 'August' THEN 1 ELSE 0 END) August, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'September' or datename(month, [CheckOut]) = 'September' THEN 1 ELSE 0 END) September, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'October' or datename(month, [CheckOut]) = 'October' THEN 1 ELSE 0 END) October, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'November' or datename(month, [CheckOut]) = 'November' THEN 1 ELSE 0 END) November, 
     SUM(CASE WHEN datename(month, [CheckIn]) = 'December' or datename(month, [CheckOut]) = 'December' THEN 1 ELSE 0 END) December 
    FROM {Booking} INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id] 
    WHERE {Booking}.[CheckIn] >= @BeginDate AND {Booking}.[CheckOut] <= @EndDate AND {Status}.[Label] <> 'Canceled' 
) monthTotals 
UNPIVOT 
(CheckIns FOR Month IN 
    (January, February, March, April, May, June, July, August, September, October, November, December) 
) AS upvt 

Here's a simplified SQLFiddle of this

И here's a doc page на PIVOT и UNPIVOT

Answer 2

Вы можете сделать ваши заявления случай немного короче/проще, так это легче читать. МЕСЯЦ() является более удобным для чтения функции и избавления от другого будет означать, если он просто возвращает нуль, который SUM() трактует как через 0

SELECT [Month], CheckIns 
FROM 
    (
    Select 
     SUM(CASE WHEN MONTH([CheckIn]) = 01 or MONTH([CheckOut]) = 01 THEN 1 END) January, 
     SUM(CASE WHEN MONTH([CheckIn]) = 02 or MONTH([CheckOut]) = 02 THEN 1 END) February, 
     SUM(CASE WHEN MONTH([CheckIn]) = 03 or MONTH([CheckOut]) = 03 THEN 1 END) March, 
     SUM(CASE WHEN MONTH([CheckIn]) = 04 or MONTH([CheckOut]) = 04 THEN 1 END) April, 
     SUM(CASE WHEN MONTH([CheckIn]) = 05 or MONTH([CheckOut]) = 05 THEN 1 END) May, 
     SUM(CASE WHEN MONTH([CheckIn]) = 06 or MONTH([CheckOut]) = 06 THEN 1 END) June, 
     SUM(CASE WHEN MONTH([CheckIn]) = 07 or MONTH([CheckOut]) = 07 THEN 1 END) July, 
     SUM(CASE WHEN MONTH([CheckIn]) = 08 or MONTH([CheckOut]) = 08 THEN 1 END) August, 
     SUM(CASE WHEN MONTH([CheckIn]) = 09 or MONTH([CheckOut]) = 09 THEN 1 END) September, 
     SUM(CASE WHEN MONTH([CheckIn]) = 10 or MONTH([CheckOut]) = 10 THEN 1 END) October, 
     SUM(CASE WHEN MONTH([CheckIn]) = 11 or MONTH([CheckOut]) = 11 THEN 1 END) November, 
     SUM(CASE WHEN MONTH([CheckIn]) = 12 or MONTH([CheckOut]) = 12 THEN 1 END) December 
    FROM [Booking] 

    INNER JOIN {Status} ON {Booking}.[StatusId] = {Status}.[Id] 
    WHERE {Booking}.[CheckIn] >= @BeginDate AND {Booking}.[CheckOut] <= @EndDate AND {Status}.[Label] <> 'Canceled' 
) MONTHTotals 
UNPIVOT 
(
CheckIns FOR [Month] IN 
    (January, February, March, April, May, June, July, August, September, October, November, December) 
) AS upvt