Question

I am trying to connect my c++ client to an PostgreSQL DB. I keep getting otlv4.h|12406|undefined reference to `SQLFreeHandle@8′ and many other undefined reference errors.

To get the header file go to http://otl.sourceforge.net/otl3_down.htm

#include <iostream>

using namespace std;

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
// #define OTL_ODBC_UNIX // uncomment this line if UnixODBC is used
#define OTL_ODBC_ALTERNATE_RPC
#if !defined(_WIN32) && !defined(_WIN64)
#define OTL_ODBC
#else
#define OTL_ODBC_POSTGRESQL // required with PG ODBC on Windows
#endif
#include "otlv4.h" // include the OTL 4.0 header file

otl_connect db; // connect object

int main()
{

    otl_connect::otl_initialize(); // initialize ODBC environment

    db.rlogon("postgres/changeme@numbers");

    db.commit();

    cout << "Hello world!" << endl;

    db.logoff(); // disconnect from ODBC
    return 0;
}

Answer 1

When I did connection from Windows to PostgreSQL using ODBC, I used DSN-less approach. It requires zero input from user perspective – user does not need to know what ODBC is and how to configure ODBC source (DSN).

Typical way to use DSN-less connection is to use string like below as your ODBC connection string:

Driver=PostgreSQL;Server=hostname;Database=mypgdb;UID=username;PWD=password

Note that driver name may need to be adjusted depending on version and ANSI vs Unicode flavors.