如何创建重复工作日作为数据透视表中的列？

Question

我是编程和数据库的新手，如果能在以下场景中得到一些帮助，我将不胜感激。

我在 SQL Server 中使用 PHP。我正在构建一个员工考勤系统，我想创建一个（枢轴）表，其中月份为行，所有工作日名称为列（针对特定年份）。单元格中的值将是天数（1、2、3...31）。

单元格的背景颜色（已作为表格列存在）声明了员工休假的类型。该表具有以下列：employee_id, leave_date, leave_type, leave_type_color.

我想达到如下结果：

谢谢你。

Answer 1

其中最复杂的部分就是以这种格式构建日历。用 HTML 旋转和包围它非常容易。首先，让我们从这个带有休假日期的员工表开始。leave_type似乎与手头的问题无关。

CREATE TABLE dbo.EmpLeave
(
  EmployeeID int,
  leave_date date,
  leave_type_color char(6)
);

INSERT dbo.EmpLeave(EmployeeID,leave_date,leave_type_color)
  VALUES(1,'2018-01-02','7777cc'),(1,'2018-04-01','ffffac');

我想出的程序看起来像这样（和警告：它假设@@DATEFIRST = 7）：

CREATE PROCEDURE dbo.BuildLeaveHTMLTable
  @EmployeeID int,
  @Year smallint = NULL
AS
BEGIN
  SET NOCOUNT ON;
  SET @Year = COALESCE(@Year, DATEPART(YEAR, GETDATE()));
  DECLARE @FirstDay date = DATEADD(YEAR, @Year-1900, 0);

  ;WITH Numbers AS ( -- 366 possible days (leap year)
    SELECT n = 1 UNION ALL SELECT n + 1 FROM Numbers WHERE n <= 365
  ),
  Calendar AS ( -- a year's worth of dates and dateparts 
    SELECT [Date] = d,
      MonthStart = DATEADD(DAY, 1-DAY(d),d),
      Y  = CONVERT(smallint, DATEPART(YEAR,   d)),
      M  = CONVERT(tinyint,  DATEPART(MONTH,  d)),
      D  = CONVERT(tinyint,  DATEPART(DAY,    d)),
      WY = CONVERT(tinyint,  DATEPART(WEEK,   d)),
      DW = CONVERT(tinyint,  DATEPART(WEEKDAY,d))
    FROM
    (
      SELECT d = CONVERT(date,DATEADD(DAY, n-1, @FirstDay)) FROM Numbers
    ) AS c WHERE YEAR(d) = @Year -- in case it's not a leap year
  ),
  BaseSlots AS ( -- base set of 37 ints 
   -- month can be spread across 6 weeks, but no more than 2 days in 6th week
    SELECT TOP (37) slot = n FROM Numbers ORDER BY n
  ),
  Months AS ( -- base set of 12 ints
    SELECT TOP (12) m = slot FROM BaseSlots ORDER BY slot
  ),
  SlotAlignment AS ( -- align days of week to slot numbers
    -- this is the most cryptic part of this solution
    -- determines which set of 7 slots, and which slot 
    -- exactly, a given date will appear under
    SELECT c.*, slot = DW+(c.WY+1-DATEPART(WEEK,c.MonthStart)-1)*7
      FROM Calendar AS c 
      INNER JOIN Months AS m ON c.M = m.m
  ),
  SlotMatrix AS ( -- extrapolate actual dates to 37 x 12 matrix
    SELECT m.m, s.slot, sa.[Date] 
      FROM BaseSlots AS s 
      CROSS JOIN Months AS m
      LEFT OUTER JOIN SlotAlignment AS sa
      ON sa.m = m.m AND sa.slot = s.slot
  ),
  FinalHTML AS ( -- build some HTML!
    SELECT m = '<!-- ' + RIGHT('0' + RTRIM(m), 2) + ' -->', 
      slot, cell = CASE WHEN slot = 1 THEN '<tr><th>' 
        + COALESCE(DATENAME(MONTH,DATEADD(MONTH, m-1, 0)),'') 
        + '</th>' ELSE '' END + '<td' + COALESCE(' bgcolor=#' 
        + RIGHT(CONVERT(varchar(10),CONVERT(varbinary(8), el.leave_type_color),1),6),
          CASE WHEN DATEPART(WEEKDAY, [Date]) IN (1,7) 
          THEN ' bgcolor=#cccccc' ELSE '' END)
        + '>' + COALESCE(RTRIM(DATEPART(DAY,[Date])), '&nbsp;')
        + '</td>' + CASE WHEN slot = 37 THEN '</tr>' ELSE '' END
      FROM SlotMatrix AS q LEFT OUTER JOIN dbo.EmpLeave AS el
      ON q.Date = el.leave_date
      AND el.EmployeeID = @EmployeeID
  ) -- now turn it sideways
  SELECT m = '<!-- 00 -->', 
    [1]  = '<tr><th>Month</th><th>S</th>',    [2]  = '<th>M</th>', 
    [3]  = '<th>T</th>', [4]  = '<th>W</th>', [5]  = '<th>T</th>', 
    [6]  = '<th>F</th>', [7]  = '<th>S</th>', [8]  = '<th>S</th>', 
    [9]  = '<th>M</th>', [10] = '<th>T</th>', [11] = '<th>W</th>',
    [12] = '<th>T</th>', [13] = '<th>F</th>', [14] = '<th>S</th>', 
    [15] = '<th>S</th>', [16] = '<th>M</th>', [17] = '<th>T</th>',
    [18] = '<th>W</th>', [19] = '<th>T</th>', [20] = '<th>F</th>', 
    [21] = '<th>S</th>', [22] = '<th>S</th>', [23] = '<th>M</th>',
    [24] = '<th>T</th>', [25] = '<th>W</th>', [26] = '<th>T</th>', 
    [27] = '<th>F</th>', [28] = '<th>S</th>', [29] = '<th>S</th>', 
    [30] = '<th>M</th>', [31] = '<th>T</th>', [32] = '<th>W</th>', 
    [33] = '<th>T</th>', [34] = '<th>F</th>', [35] = '<th>S</th>',
    [36] = '<th>S</th>', [37] = '<th>M</th>'
  UNION ALL
  (
    SELECT * FROM FinalHTML PIVOT (MAX(cell) FOR slot IN 
    (
     [1], [2], [3], [4], [5], [6], [7], [8], [9], [10],[11],[12],[13],[14],
     [15],[16],[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27],[28],
     [29],[30],[31],[32],[33],[34],[35],[36],[37]
    )) AS p
  )
  ORDER BY m OPTION (MAXRECURSION 366);
END
GO

此调用的结果：

EXEC dbo.BuildLeaveHTMLTable @EmployeeID = 1;

看起来像这样（我停在第 7 天栏）：

您必须自己添加<table>/</table>包装器，但这是放在它们之间并保存为 HTML 时输出的样子（当然，您可以使用 CSS 进一步增强它）：

当休假在周末时，休假颜色胜过周末颜色，但这很容易调整。改变这个：

  + COALESCE(' bgcolor=#' + RTRIM(el.leave_type_color),
      CASE WHEN DATEPART(WEEKDAY, [Date]) IN (1,7) 
      THEN ' bgcolor=#cccccc' ELSE '' END)

对此：

  + CASE WHEN DATEPART(WEEKDAY, [Date]) IN (1,7) 
      THEN ' bgcolor=#cccccc' ELSE COALESCE(' bgcolor=#' 
      + RTRIM(el.leave_type_color), '') END

要将十进制格式（如65280）的颜色转换为其等效的 RGB ( 00FF00)，您必须进行大量操作。我首先会考虑将它存储为 RGB 十六进制，但我在这里用类似的东西更新了解决方案：

SELECT RIGHT(CONVERT(varchar(10),CONVERT(varbinary(8), 65280),1),6);