#include    <Windows.h>
#include    <sql.h>
#include    <sqlext.h>
#include    <sqltypes.h>
#include    <stdio.h>

//
// function prototypes
//
int main();

//
// main
//
int main()
{
    SQLHENV         henv;
    SQLHDBC         hdbc;
    SQLHSTMT        hstmt;
    SQLRETURN       sqlrc;
    char            sql[1025];
    char            svalue[2049];
    SQLINTEGER      inum;
    SQLSMALLINT     cols;
    int             i;
    char            uid[24];
    char            pwd[24];
    char            dsn[24];

    // connection strings
    strcpy(uid, "uid");
    strcpy(pwd, "pwd");
    strcpy(dsn, "dsn");

    // SQL strings
    strcpy(sql, "select * from kemp");

    // environment handle
    sqlrc = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLAllocHandle SQL_HANDLE_ENV Error\n");
        return 9;
    }

    // environment variables settings
    sqlrc = SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void *)SQL_OV_ODBC3, 0);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLSetEnvAttr Error\n");
        return 9;
    }

    // connection handle
    sqlrc = SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLAllocHandle SQL_HANDLE_DBC Error\n");
        return 9;
    }

    // connect
    sqlrc = SQLConnect(hdbc, (SQLCHAR*)dsn, SQL_NTS, (SQLCHAR*)uid, SQL_NTS, (SQLCHAR*)pwd, SQL_NTS);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLConnect Error\n");
        return 9;
    }

    // statement handle
    sqlrc = SQLAllocHandle(SQL_HANDLE_STMT, hdbc, &hstmt);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLAllocHandle SQL_HANDLE_STMT Error\n");
        return 9;
    }

    // statement prepare
    sqlrc = SQLPrepare(hstmt, (SQLCHAR*)sql, SQL_NTS);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLPrepare Error\n");
        return 9;
    }

    // get result columns
    sqlrc = SQLNumResultCols(hstmt, &cols);
    if (sqlrc != SQL_SUCCESS && sqlrc != SQL_SUCCESS_WITH_INFO) {
        printf("SQLNumResultCols Error\n");
        return 9;
    }

    // execute
    sqlrc = SQLExecDirect(hstmt, (SQLCHAR*)sql, SQL_NTS);

    // display result in CSV format
    while (TRUE) {
        sqlrc = SQLFetch(hstmt);

        if (sqlrc == SQL_SUCCESS || sqlrc == SQL_SUCCESS_WITH_INFO) {
            for (i = 1; i < cols+1; i++) {
                if (i > 1) {printf(",");}
                strcpy(svalue, "");
                SQLGetData(hstmt, i, SQL_C_CHAR, (SQLCHAR*)svalue, 2048, &inum);
                printf(svalue);
            }
            printf("\n");
        } else {
            if (sqlrc == SQL_NO_DATA) {
                printf("\n");
            } else {
                // otherwise error
                printf("SQLFetch ERROR\n");
            }
            break;
        }
    }
}