OCCI create environment

I am new to OCCI and am using VS.NET to access Oracle database. I am having problems with the createConnection call. When I execute the program I get the following error "An unhandled exception of type 'System.NullReferenceException' occurred in database.exe Additional Information: Object reference not set to an instance of an object" And it points to this line conn = env->createConnection (user, passwd, db); This is one of oracle's examples and I don't understand why the string db is "" I would think it would have information on the database you are trying to access. Any suggestions? Thanks.
#include <iostream>

#include <occi.h>

using namespace oracle::occi;

using namespace std;

class occidml

{

private:

Environment *env;

Connection *conn;

Statement *stmt;

public:

occidml (string user, string passwd, string db)

{

env = Environment::createEnvironment (Environment::DEFAULT);

conn = env->createConnection (user, passwd, db);

}

~occidml ()

{

env->terminateConnection (conn);

Environment::terminateEnvironment (env);

}

int main (void)

{

string user = "own";

string passwd = "own";

string db = "";

cout << "occidml - Exhibiting simple insert, delete & update operations"

<< endl;

occidml *demo = new occidml (user, passwd, db);

} Received on Thu Nov 13 2003 - 11:47:28 CST