Question

为什么动态SQL不起作用？

C＃中的代码：

 this.DataAccess.AddParametr("@where","WHERE ta.IdMoinRef in(112,113,115)");

sqlServer中的代码：

ALTER Procedure [dbo].[sp_tblAsnad_SelectAllForReport]
@where nvarchar(max)
As
Begin                                       
Select
        ta.IdMoinRef,
        ta.IdTafzeliRef,
        ta.ShHesab,
        ta.Bd,
        ta.Bs,
        ta.ShSnd,
        ta.AtfSnd,
        ta.DateSnd,
        mo.Hmoin,
        co.Hcol,
        gr.Hgroup,
        co.IdGroupRef,
        mo.IdColRef
    From tblAsnad as ta
    inner join tblMoin as mo on ta.IdMoinRef=mo.IdMoin
    inner join tblCol as co on mo.IdColRef=co.IdCol
    inner join tblGroup as gr on co.IdGroupRef=gr.IdGroup
    exec(@where)
End

Answer 1

你很困惑。您需要将整个语句封装到命令中。您正在尝试执行一个查询，然后执行其他查询。您需要将您的主查询与您的参数一起解析，例如

DECLARE @sql VARCHAR(1000)
SET @sql = "SELECT ... " + @where -- Your full query.
exec(@sql)

Answer 2

您尝试仅执行where子句。对于动态SQL语句，必须将整个语句构建为字符串：

           @s = "select * from T " + @where_clause
           exec(@s)

Answer 3

您需要将整个查询作为一个字符串执行，而不仅仅是WHERE子句。

Answer 4

您的代码将WHERE字符串作为字符串参数传递。那么你的proc将执行的将是：

ALTER Procedure [dbo].[sp_tblAsnad_SelectAllForReport]
@where nvarchar(max)
As
Begin                                       
Select
        ta.IdMoinRef,
        ta.IdTafzeliRef,
        ta.ShHesab,
        ta.Bd,
        ta.Bs,
        ta.ShSnd,
        ta.AtfSnd,
        ta.DateSnd,
        mo.Hmoin,
        co.Hcol,
        gr.Hgroup,
        co.IdGroupRef,
        mo.IdColRef
    From tblAsnad as ta
    inner join tblMoin as mo on ta.IdMoinRef=mo.IdMoin
    inner join tblCol as co on mo.IdColRef=co.IdCol
    inner join tblGroup as gr on co.IdGroupRef=gr.IdGroup
    exec('WHERE ta.IdMoinRef in(112,113,115)')
End

哪个，显然是错的。您的整个命令需要在此处的命令文本中。

为什么动态SQL不起作用

4 个答案: