我试图从用C++编写的控制台应用程序调用我的Microsoft SQL Server上的用户定义函数。整个事情我都用ADO。如何使用ADO从C++调用用户定义的函数
我的功能看起来像这样(和它的作品时,我用它从Management Studio中)
CREATE FUNCTION [dbo].[funcHowOftenDidHeWin]
(
@playername as varchar(15)
@percentWon float OUTPUT
)
RETURNS float
AS
BEGIN
DECLARE @wintimes float
DECLARE @participated float
DECLARE @percentWon float
SELECT @wintimes = COUNT(DidWin)
FROM PPLP0p02
WHERE DidWin = 1 AND [email protected]
SELECT @participated = COUNT(DidWin)
FROM PPLP0p02
WHERE Playername = @playername
IF @wintimes >0
SET @percentWon = @wintimes/@participated *100
IF @wintimes = 0
SET @percentWon = 0
RETURN @percentWon
END
GO
从我的节目,我尝试调用它,如下所示:
USEADO::_ConnectionPtr connection;
USEADO::_RecordsetPtr recordset; //create a "
if(FAILED(hr = CoInitialize(NULL))) //
{ return hr;}
if(FAILED(hr = connection.CreateInstance(__uuidof(USEADO::Connection))))
{ return hr;}
if(FAILED(hr = recordset.CreateInstance(__uuidof(USEADO::Recordset))))
{ return hr;}
connection->CursorLocation = USEADO::adUseServer;
try
{
connection->Open(L"Provider=SQLOLEDB.1;Persist Security Info=False;User ID=Test;Initial Catalog=Haufen;Data Source=Wolle\\SQLEXPRESS", L"Test", L"Test", USEADO::adConnectUnspecified);
}
catch(...) {std::cout << "!!! connection->Open(ConnectionString FAILED !!!" << std::endl; }
//This works
recordset->Open("SELECT playername FROM Summary WHERE playersatbegin=5",connection.GetInterfacePtr(),adOpenDynamic,adLockOptimistic,adCmdText);
//This not
recordset->Open("SELECT dbo.funcHowOftenDidHeWin('Lumpi') ",connection.GetInterfacePtr(),adOpenDynamic,adLockOptimistic,adCmdText);
好,这是行不通的。调试器以1580行的masado15.tli结尾,VS显示一个窗口,其中包含以下错误:35h.exe中的0x7c812afb处未处理的异常:Microsoft C++异常:内存位置0x0012c3f8处的_com_error。
我不知道如果语法是正确的,我不知道该服务器应该如何从我想要的结果的表就知道....
任何帮助在那里?谢谢
Lumpi
你有错误吗?如果是这样......将其粘贴在这里。 – garnertb 2011-05-24 22:17:00
错误是:35h.exe中0x7c812afb未处理的异常:Microsoft C++异常:_com_error在内存位置0x0012c3f8 .. – Lumpi 2011-05-25 18:30:25