Connecting to Oracle Problem

Let me preface by saying Im not really a C programmer. More of a vb programmer doing .net stuff, but someone got word i did a little c back in college some 10 years ago and threw this at me. so im not really comfortable or sure i know what im doing.

they are trying to connect to an oracle database we have here. using that data source, username, and pass in the connstring i can connect to the database using sql+. The code they gave me was a mess, so ive cleaned it up a bit and finally got it to compile. it crashes on the pConnection->Open line, and my catch message simple says "Invalid Pointer". Ive found a lot of very similar code on the net so I know im not doing anything too unordinary. Any ideas or can someone please point me in the right direction?

Thanks

Code:

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#include <iostream>
#include <stdio.h>
#include <windows.h>

#import "C:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF", "EndOfFile")

//#include "c:\oracle\ora92\oo4o\CPP\include\ORACL.H"
//#include "c:\oracle\ora92\oledb\include\oraoledb.h"

using namespace std;

void main()
{   
        HRESULT hr = S_OK;

        _ConnectionPtr pConnection = NULL;

        _bstr_t strCnn("Provider=OraOLEDB.Oracle;PLSQLRSet=1;USER Id=UPTS_TEST;Password=UPTS_TEST;Data Source=DVLP9;");

    try
    {
        /* create an instance of connection object */

        //TESTHR (pConnection.CreateInstance(__uuidof(Connection)));     

        /* open the connection */
                hr = pConnection.CreateInstance(__uuidof(Connection));
                cout << "before connect\n";
        hr = pConnection->Open(strCnn,"","",adConnectUnspecified); 
                cout << "after connect\n";
        if (hr == S_OK)
            cout << "connected\n";
        else
            cout << "not connected\n"; 
                pConnection->Close();
        }
        catch(_com_error &ce)
    {
                printf("Description = %s\n", (char*) ce.ErrorMessage());
    }
}

---

Code:

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hr = pConnection.CreateInstance(__uuidof(Connection));

---

Set a breakpoint on the line after this one, debug and tell me what the values of hr and pConnection are.

Does this even compile?
hr = pConnection.CreateInstance // using dot
hr = pConnection->Open // using arrow

Also, it's C++, not C.
C doesn't have try/catch, namespaces or cout. Moved to C++ board.

Quote:

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Originally Posted by Salem

Does this even compile?

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Welcome to the wacky world of COM objects. ;)

RvS, after looking through some old code of mine, I believe you are missing:-

Code:

---

CoInitialize(NULL);

---

At the start of main and

Code:

---

CoUninitialize();

---

at the end.

very good. i will try that first thing in the morning. thanks so much

The reason why you are getting an invalid pointer, is that the pointer isn't initiated via createinstance():
HRESULT hr = pConnection->CreateInstance(__uuidof(ADODB::Connection));

Quote:

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Originally Posted by SMurf

Welcome to the wacky world of COM objects. ;)

RvS, after looking through some old code of mine, I believe you are missing:-

Code:

---

CoInitialize(NULL);

---

At the start of main and

Code:

---

CoUninitialize();

---

at the end.

---

SMurf,
worked like a charm, thanks so much!