Сортировка производного столбца в оконном запросе

Question

У меня есть оконный запрос, как показано ниже:

SELECT * 
FROM 
    (
     SELECT COUNT(*) OVER (PARTITION BY NULL) AS TotalRows, 
     ROW_NUMBER() OVER 
     (
      ORDER BY MyDerivedColumn asc 
     ) AS RowNumber 
     ,MyDerivedColumn = (SELECT TOP 1 SomeColumn FROM SomeTable ORDER BY SomeOtherColumn DESC) 
      ... 

и я не могу получить его на заказ в производных столбцов (как показано выше). Я был в состоянии сделать заказ производных столбцами с помощью «обычных» запросов с помощью индекса столбца в порядке п IE:

ORDER BY 2 

, но я получаю сообщение об ошибке при попытке выполнить свой оконный запрос, который говорит:

Windowed functions do not support integer indices as ORDER BY clause expressions.

Как я могу заказать производные столбцы, как указано выше?

ТИА

EDIT: Проводка мой фактический код для каждого запроса.

SET @SQL = ' 
SELECT * 
FROM 
    (
     SELECT COUNT(*) OVER (PARTITION BY NULL) AS TotalRows, 
     ROW_NUMBER() OVER 
     (
      ORDER BY StudentDissertationStageDescription ASC 
     ) AS RowNumber, 
     sc.FirstName 
     ,sc.LastName 
     ,sc.StudentId 
     ,spos.ProgramOfStudy AS ProgramOfStudy 
     ,(
      SELECT TOP 1 [StudentDissertationStageDescription] 
      FROM 
       [StudentDissertationStage] AS sd 
      WHERE sc.StudentId = sd.StudentId 
      ORDER BY sd.[StudentDissertationStage] DESC 
     ) AS StudentDissertationStageDescription 
    FROM 
     StudentClasses AS sc 
    LEFT JOIN 
     StudentProgramOfStudy AS spos 
    ON 
     spos.StudentId = sc.StudentId 
    LEFT JOIN [dbo].[FacultyAssignments] fa 
     ON sc.StudentId = fa.StudentID 
    WHERE 1 = 1 
    ' 
    IF @filter IS NOT NULL 
    BEGIN 
     SET @SQL = @SQL + @filter 
    END 
    SET @SQL = @SQL + ' 
    GROUP BY 
     sc.FirstName 
     ,sc.LastName 
     ,sc.SyStudentID 
     ,spos.ProgramOfStudy 
    ) AS TheTableSet 
    WHERE 
     RowNumber BETWEEN ' + 
     CONVERT(nvarchar(10), @startrow) + 
     ' AND ' + 
     CONVERT(nvarchar(10), @endrow) + '' 
    EXEC(@SQL) 

Answer 1

Это то, что вы хотите?

;with cte as (
    select 
     1 as num, 
     (SELECT TOP 1 SomeColumn FROM SomeTable ORDER BY SomeOtherColumn DESC) as MyDerivedColumn 
) 
SELECT 
    COUNT(*) OVER (PARTITION BY NULL) AS TotalRows, 
    ROW_NUMBER() OVER (ORDER BY MyDerivedColumn asc) AS RowNumber 
FROM cte 

Вы также можете написать этот запрос с подзапроса:

SELECT 
    COUNT(*) OVER (PARTITION BY NULL) AS TotalRows, 
    ROW_NUMBER() OVER (ORDER BY MyDerivedColumn asc) AS RowNumber 
FROM (
    select 
     1 as num, 
     (SELECT TOP 1 SomeColumn FROM SomeTable ORDER BY SomeOtherColumn DESC) as MyDerivedColumn 
) t 

Таким образом, ваш код будет выглядеть примерно так:

SET @SQL = ' 
SELECT * 
FROM 
    (
     SELECT 
      COUNT(*) OVER (PARTITION BY NULL) AS TotalRows, 
      ROW_NUMBER() OVER (ORDER BY StudentDissertationStageDescription ASC) AS RowNumber, 
      sc.FirstName, 
      sc.LastName 
      sc.StudentId 
      spos.ProgramOfStudy AS ProgramOfStudy 
     FROM (
      sc.FirstName, 
      sc.LastName, 
      sc.StudentId, 
      spos.ProgramOfStudy AS ProgramOfStudy, 
      (
       SELECT TOP 1 [StudentDissertationStageDescription] 
       FROM [StudentDissertationStage] AS sd 
       WHERE sc.StudentId = sd.StudentId 
       ORDER BY sd.[StudentDissertationStage] DESC 
      ) AS StudentDissertationStageDescription, 
      DissertationChair = staff.[FirstName] + '' '' + staff.[LastName], 
      DissertationEmail = staff.[email] 
      FROM StudentClasses AS sc 
      LEFT JOIN StudentProgramOfStudy AS spos ON spos.StudentId = sc.StudentId 
      LEFT JOIN [dbo].[FacultyAssignments] fa ON sc.StudentId = fa.StudentID 
      WHERE 1 = 1 
      ' 
      IF @filter IS NOT NULL 
      BEGIN 
       SET @SQL = @SQL + @filter 
      END 
      SET @SQL = @SQL + ' 
     ) t 
     GROUP BY 
      t.FirstName, 
      t.LastName, 
      t.SyStudentID, 
      t.ProgramOfStudy 
    ) AS TheTableSet 

    WHERE 
     RowNumber BETWEEN ' + CONVERT(nvarchar(10), @startrow) + ' AND ' + CONVERT(nvarchar(10), @endrow) 

EXEC(@SQL)