需要幫助與sql查詢

Question

我需要幫助的查詢。在我的查詢中，我想通過我的表名作爲參數。這是我的查詢：

SELECT DISTINCT 
    CONVERT (varchar, InspectDateTime) AS 'Inspect Date Time', 
    CONVERT (varchar, SynDateTime) AS 'Sync Date Time', 
    Employee, 
    ROUND(OverAllPercentage, 2) AS Grade 
FROM 
    Table_Name 
WHERE 
    (DATEADD(dd, DATEDIFF(dd, 0, InspectDateTime), 0) 
    BETWEEN 
     DATEADD(dd, DATEDIFF(dd, 0, @From), 0) AND 
     DATEADD(dd, DATEDIFF(dd, 0, @To), 0)) 
ORDER BY 
    'Inspect Date Time' 

在這裏，我想通過Table_Name作爲參數。請注意，這個查詢已經以兩個aurguments作爲參數，即"@From「和」 @To「

問候 阿卜杜拉

Answer 1

如果您正在使用MS SQL工作，你可以這樣做：

CREATE PROCEDURE sp_GetMyStuff 
(
    @From datetime, 
    @To datetime, 
    @TableName nvarchar(100) 
) 
AS 

exec('  
    SELECT DISTINCT 
     CONVERT (varchar, InspectDateTime) AS ''Inspect Date Time'', 
     CONVERT (varchar, SynDateTime) AS ''Sync Date Time'', 
     Employee, 
     ROUND(OverAllPercentage, 2) AS Grade 
    FROM 
     ' + @TableName + ' 
    WHERE 
     (DATEADD(dd, DATEDIFF(dd, 0, InspectDateTime), 0) 
     BETWEEN 
      DATEADD(dd, DATEDIFF(dd, 0, ' + @From + '), 0) AND 
      DATEADD(dd, DATEDIFF(dd, 0, ' + @To + '), 0)) 
    ORDER BY 
     1 
'); 

，然後叫它

sp_GetMyStuff '2011-05-05', '2011-06-05', 'TBL_MYTABLE' 

Answer 2

在SQL Server中，如果你想‘參數多態’的表名，您必須使用動態SQL

如果是這樣，你必須閱讀厄蘭的The Curse and Blessing of dynamic SQL作爲一個前奏。

因此，基本上，你需要建立你的SQL語句作爲字符串，然後執行它。該re是沒有其他方式在SQL Server T-SQL語句中「參數化」表名。

Answer 3

OK，假設你使用SQL Server（由DATEADD和DATEDIFF功能判斷），你需要

1. 構建串聯SQL命令 作爲字符串（注意不要讓 SQL注入：也就是說，你應該通過查找 可能的名字形成 information_schema和驗證 等檢查 您table_name變量是 有效的表名）

2. 執行使用 sp_executesql您的動態SQL：http://msdn.microsoft.com/en-us/library/ms188001.aspx

Answer 4

謝謝balexandre。小修改（鑄造@ From，@ To into varchar）後的最終查詢是：

CREATE PROCEDURE sp_GetMyStuff 

@TableName VARCHAR(128), 
@From DATETIME, 
@To DATETIME 

AS 

DECLARE @sql VARCHAR(4000) 
SELECT @sql = 'SELECT DISTINCT CONVERT (varchar, InspectDateTime) AS ''Inspect Date Time'', CONVERT (varchar, SynDateTime) AS ''Sync Date Time'', Employee, ROUND(OverAllPercentage, 2) AS Grade 
FROM ' + @TableName + ' 
WHERE 
(DATEADD(dd, DATEDIFF(dd, 0, InspectDateTime), 0) BETWEEN DATEADD(dd, DATEDIFF(dd, 0,'''+ CAST(@From AS VARCHAR(100)) +'''), 0) 
AND DATEADD(dd, DATEDIFF(dd, 0,'''+ CAST(@To AS VARCHAR(100)) +'''), 0)) 
ORDER BY ''Inspect Date Time''' 
EXEC (@sql) 

GO