爲每條記錄選擇多條記錄

Question

我在寫一條sql語句，用戶應該輸入'From Date'和'To Date'（小於31天） 對於每個Date我需要從表中選擇與員工

我需要一個簡單的方法的邏輯..應該有一段時間了？

我這個查詢得到最新名單：

DECLARE @date TABLE(d DATETIME) 

DECLARE @d DATETIME 
SET @d = '20090101' 

WHILE @d <= '20090102' BEGIN 

    INSERT INTO @date VALUES (@d) 
    SET @d = @d + 1 

END 

SELECT d AS DateCol, dbo.ta_DayOfWeek(d) AS Day, 
DATENAME(weekday, DATEADD(day,0,d)) AS DayName FROM @date 

，這些都是一些領域，我需要使用的每一條記錄：

SELECT ta_timecard.EmpID , 
     emp.name , 
     emp.code , 
     ta_timecard.schedindate--, 
FROM ta_timecard 
INNER JOIN emp ON ta_timecard.empid = emp.id 
WHERE ta_timecard.schedindate BETWEEN @FromDate AND @ToDate 
GROUP BY ta_timecard.EmpID , 
     emp.name , 
     emp.code , 
     ta_timecard.schedindate 

在此先感謝。

Answer 1

嘗試這一個 -

查詢：

DECLARE 
     @DateFrom DATETIME 
    , @DateTo DATETIME 

SELECT 
     @DateFrom = '20130101' 
    , @DateTo = '20130202' 

SELECT 
     DateCol 
    , [DayName] = DATENAME(WEEKDAY, DateCol) 
    , [Day] = DATEPART(WEEKDAY, DateCol) 
FROM (
    SELECT DateCol = DATEADD(DAY, sv.number, t.DateFrom) 
    FROM (
     SELECT 
       DateFrom = @DateFrom 
      , diff = DATEDIFF(DAY, @DateFrom, @DateTo) 
    ) t 
    JOIN [master].dbo.spt_values sv ON sv.number <= diff 
    WHERE sv.[type] = 'p' 
) t2 

輸出：

DateCol     DayName      Day 
----------------------- ------------------------------ ----------- 
2013-01-01 00:00:00.000 Tuesday      3 
2013-01-02 00:00:00.000 Wednesday      4 
2013-01-03 00:00:00.000 Thursday      5 
2013-01-04 00:00:00.000 Friday       6 
2013-01-05 00:00:00.000 Saturday      7 
2013-01-06 00:00:00.000 Sunday       1 
2013-01-07 00:00:00.000 Monday       2 
2013-01-08 00:00:00.000 Tuesday      3 
.... 
2013-01-31 00:00:00.000 Thursday      5 
2013-02-01 00:00:00.000 Friday       6 
2013-02-02 00:00:00.000 Saturday      7 

更新（PIVOT +動態SQL）：

SET NOCOUNT ON; 

DECLARE 
     @DateFrom DATETIME 
    , @DateTo DATETIME 

SELECT 
     @DateFrom = '20130501' 
    , @DateTo = '20130515' 

DECLARE @SQL_Pivot NVARCHAR(MAX) 
SELECT @SQL_Pivot = STUFF((
    SELECT ', [' + 
     CONVERT(VARCHAR(8), DateCol, 1) + 
     ' ' + 
     LEFT(DATENAME(WEEKDAY, DateCol), 3) + ']' 
    FROM (
     SELECT DateCol = DATEADD(DAY, sv.number, t.DateFrom) 
     FROM (
      SELECT 
        DateFrom = @DateFrom 
       , diff = DATEDIFF(DAY, @DateFrom, @DateTo) 
     ) t 
     JOIN [master].dbo.spt_values sv ON sv.number <= diff 
     WHERE sv.[type] = 'p' 
    ) t 
    FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, '') 

IF OBJECT_ID(N'tempdb.dbo.#emp') IS NOT NULL 
    DROP TABLE tempdb.dbo.#emp 

CREATE TABLE #emp 
(
     EmpID INT PRIMARY KEY 
    , Name NVARCHAR(50) 
) 

INSERT INTO #emp (EmpID, Name) 
VALUES (1, N'Nejthe'), (2, N'DevArt') 

IF OBJECT_ID(N'tempdb.dbo.#timecard') IS NOT NULL 
    DROP TABLE tempdb.dbo.#timecard 

CREATE TABLE #timecard 
(
     EmpID INT 
    , ScheduleDate DATETIME 
) 

INSERT INTO #timecard (EmpID, ScheduleDate) 
VALUES 
     (1, '2013-05-02 13:20:08') 
    , (2, '2013-05-01 14:24:34') 
    , (1, '2013-05-01 13:34:07') 
    , (1, '2013-05-05 12:20:48') 
    , (2, '2013-05-08 17:20:48') 

DECLARE @SQL NVARCHAR(MAX) 
SELECT @SQL = ' 
SELECT * 
FROM (
    SELECT 
      t.EmpID 
     , e.Name 
     , OnlyTime = CONVERT(VARCHAR(10), t.ScheduleDate, 108) 
     , OnlyDate = CONVERT(VARCHAR(8), t.ScheduleDate, 1) + '' '' + LEFT(DATENAME(WEEKDAY, ScheduleDate), 3) 
    FROM #timecard t 
    JOIN #emp e ON t.EmpID = e.EmpID 
) o 
PIVOT 
(
    MIN(o.OnlyTime) 
    FOR o.OnlyDate IN (' + @SQL_Pivot + ') 
) pt 
ORDER BY EmpID' 

EXEC sys.sp_executesql @SQL 

輸出：

EmpID Name  05/01/13 Wed 05/02/13 Thu 05/03/13 Fri 05/04/13 Sat 05/05/13 Sun 05/06/13 Mon 05/07/13 Tue 05/08/13 Wed 05/09/13 Thu 05/10/13 Fri 05/11/13 Sat 05/12/13 Sun 05/13/13 Mon 05/14/13 Tue 05/15/13 Wed 
------ --------- ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ ------------ 
1  Nejthe 13:34:07  13:20:08  NULL   NULL   12:20:48  NULL   NULL   NULL   NULL   NULL   NULL   NULL   NULL   NULL   NULL 
2  DevArt 14:24:34  NULL   NULL   NULL   NULL   NULL   NULL   17:20:48  NULL   NULL   NULL   NULL   NULL   NULL   NULL