需要帮助与sql查询

Question

我需要帮助的查询。在我的查询中，我想通过我的表名作为参数。这是我的查询：

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' 

在这里，我想通过Table_Name作为参数。请注意，这个查询已经以两个aurguments作为参数，即"@From“和” @To“

问候 阿卜杜拉

Answer 1

如果您正在使用MS SQL工作，你可以这样做：

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 
'); 

，然后叫它

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

Answer 2

在SQL Server中，如果你想‘参数多态’的表名，您必须使用动态SQL

如果是这样，你必须阅读厄兰的The Curse and Blessing of dynamic SQL作为一个前奏。

因此，基本上，你需要建立你的SQL语句作为字符串，然后执行它。该re是没有其他方式在SQL Server T-SQL语句中“参数化”表名。

Answer 3

OK，假设你使用SQL Server（由DATEADD和DATEDIFF功能判断），你需要

1. 构建串联SQL命令 作为字符串（注意不要让 SQL注入：也就是说，你应该通过查找 可能的名字形成 information_schema和验证 等检查 您table_name变量是 有效的表名）

2. 执行使用 sp_executesql您的动态SQL：http://msdn.microsoft.com/en-us/library/ms188001.aspx

Answer 4

谢谢balexandre。小修改（铸造@ From，@ To into varchar）后的最终查询是：

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