问题和Sql动态查询

Question

我想写一个动态sql.following是我的存储过程，它的具有附加的SQL查询来@SQLSTATEMENT能有人帮我解决这个错误？它显示+标记

EX下错误 - SET @SQLSTATEMENT +'AND TA.AreaID='+@AreaID+'

ALTER PROCEDURE spGetOverDueDocuments 
@AreaID INT =NULL, 
@DepartmentID INT= NULL, 
@ABSID INT =NULL, 
@DisciplineID INT = NULL, 
@CPOID INT = NULL, 
@DocumentTypeID INT = NULL, 
@DueType VaRCHAR(20) = NULL 
AS 
BEGIN 
DECLARE @SQLSTATEMENT VARCHAR(MAX) 


SELECT @SQLSTATEMENT = 'SELECT * '+ 
'FROM tblActionHeader AH INNER JOIN '+ 
'tblDocumentRevisionActionHeader DAH ON AH.ActionHeaderID=DAH.ActionHeaderID INNER JOIN '+ 
'tblDocumentRevision DR ON DAH.DocumentRevisionID=DR.DocumentRevisionID INNER JOIN '+ 
'tblDocumentHeader DH ON DR.DocumentHeaderID=DH.DocumentHeaderID INNER JOIN tblABS TB ON DH.ABSID=TB.ABSID ' + 
'INNER JOIN tblArea TA ON TA.AreaID=TB.AreaNo INNER JOIN tblContractPODocumentHeader CDH ON '+ 
' CDH.DocumentHeaderID=DH.DocumentHeaderID INNER JOIN tblDiscipline DC ON '+ 
' DH.DisciplineID=DC.DisciplineID INNER JOIN tblContractPO CPO ON CPO.CPOID=DH.CPOID INNER JOIN tblDocumentType DT '+ 
' ON DT.DocumentTypeID=DH.DocumentTypeID '+ 
'WHERE AH.ActionTypeID=4 ' 
IF @AreaID<>'0' 
BEGIN 
SET @SQLSTATEMENT + ' AND TA.AreaID='+@AreaID+' ' 
END 

IF @ABSID<>'0' 
BEGIN 
SET @SQLSTATEMENT + ' AND TB.ABSID='+@ABSID+' ' 
END 

IF @DisciplineID<>'0' 
BEGIN 
SET @SQLSTATEMENT + ' AND DC.DisciplineID='+@DisciplineID+' ' 
END 

IF @CPOID<>'0' 
BEGIN 
SET @SQLSTATEMENT + ' AND CPO.CPOID='+@CPOID+' ' 
END 

IF @DocumentTypeID<>'0' 
BEGIN 
SET @SQLSTATEMENT + ' AND DT.DocumentTypeID='+@DocumentTypeID+' ' 
END 

EXEC(@SQLSTATEMENT) 

END 

Answer 1

尝试

SET @SQLSTATEMENT = @SQLSTATEMENT + <rest> 

即

SET @SQLSTATEMENT = @SQLSTATEMENT + ' AND TA.AreaID='+STR(@AreaID)+' ' 

Answer 2

@Area ID被声明为INT，你需要将其转换为varchar为了能够将其追加。

试试这个：

SET @SQLSTATEMENT + ' AND TA.AreaID='+cast(@AreaID as varchar(30))+' ' 

Answer 3

另一种选择是使用不需要动态SQL查询

一种可能的方式做到这一点是：

SELECT * 
FROM tblActionHeader AH 
INNER JOIN tblDocumentRevisionActionHeader DAH ON AH.ActionHeaderID=DAH.ActionHeaderID 
INNER JOIN tblDocumentRevision DR ON DAH.DocumentRevisionID=DR.DocumentRevisionID 
INNER JOIN tblDocumentHeader DH ON DR.DocumentHeaderID=DH.DocumentHeaderID 
INNER JOIN tblABS TB ON DH.ABSID=TB.ABSID 
INNER JOIN tblArea TA ON TA.AreaID=TB.AreaNo 
INNER JOIN tblContractPODocumentHeader CDH ON CDH.DocumentHeaderID=DH.DocumentHeaderID 
INNER JOIN tblDiscipline DC ON DH.DisciplineID=DC.DisciplineID 
INNER JOIN tblContractPO CPO ON CPO.CPOID=DH.CPOID 
INNER JOIN tblDocumentType DT ON DT.DocumentTypeID=DH.DocumentTypeID 
WHERE TA.AreaID = (CASE WHEN @AreaID<>'0' THEN @AreaID ELSE TA.AreaId END) 
AND TA.ABSID = (CASE WHEN @ABSID<>'0' THEN @ABSID ELSE TA.ABSID END) 
AND DC.DisciplineID = (CASE WHEN @DisciplineID<>'0' THEN @DisciplineID ELSE DC.DisciplineID END) 
AND CPO.CPOID = (CASE WHEN @CPOID<>'0' THEN @CPOID ELSE TA.ABSID END) 
AND DT.DocumentTypeID = (CASE WHEN @DocumentTypeID<>'0' THEN @DocumentTypeID ELSE TA.ABSID END) 

在此查询中，您动态添加的搜索谓词现在设置为与自己进行比较，除非指定了另一个值。只要它们中的任何一个都为null（因为测试NULL = NULL或NULL = x将始终为假），这将工作。

这很可能导致更好的查询可以被缓存和重用。但需要注意的一点是参数嗅探：如果您在所有参数= 0的情况下首次运行此SP，则优化器将选择（并缓存）一个非常不同的执行计划，而不是大多数参数都不为零。