Troubleshooting SQL Server connection in C++ using Visual Studio Express 2013 - c++

Question

I've been trying to get a simple program together that can perform some simple operations on a SQL Server database, but can't get any of the tutorials to actually run. I'm trying to figure out if the problem is with the code or with my ODBC settings. Any help/insight is greatly appreciated.
EDIT/UPDATE: ADDITIONAL DETAIL & CODE BELOW
The main program right now is based on this tutorial. I had to make a few changes so that VS Express 2013 would compile the code:
All instances of SQLCHAR * had to be changed to SQLWCHAR *.Had to use wcout to output the error messagesThe 'GOTO: FINISHED' used in the tutorial generated errors that the objects might be uninitialized. I added an 'UNFIN' block after 'FINISHED' and changed those generating errors to GOTO UNFIN to make the compier happyAdded a few debugging markers to make sure I was following the program properlyChanged the connection string to match the server, username and password of the database I'm trying to connect to. Note: Target database uses SQLServer2008
On running the program, I get the following error message (generated by the show_error() function):
Messsage: [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified
nSQLSTATE: IM002
Could it be something as simple as an ODBC setting that I need to toggle on my machine or a dependency I've missed in the project setup?
Here's the code. (Note that there are extra headers for other features being tested. Said other features are commented out in my current test program and deleted from the below copy-paste to reduce confusion)
#include "stdafx.h"
#include <stdio.h>
#include <string>
#include <sstream>//Used to int to string, and string to int operations
#include <stdlib.h>
#include <fstream>//Used for file opening, appending and writing operations
#include <iostream>
#include <Windows.h>//Used for sleep command, and window "clearwindow" function
#include <sqlext.h> // Used for writing to SQL database
#include <sqltypes.h>
#include <sql.h>
using namespace std;
void show_error(unsigned int handletype, const SQLHANDLE& handle){
SQLWCHAR sqlstate[1024];
SQLWCHAR message[1024];
cout << "In show_error" << endl;
if (SQL_SUCCESS == SQLGetDiagRec(handletype, handle, 1, sqlstate, NULL, message, 1024, NULL)){
cout << "Message: ";
wcout << message;
cout << endl << "nSQLSTATE: ";
wcout << sqlstate;
cout << endl;
}
}
bool write_to_database(/*string dbconnection, string fields, string values*/){
SQLHANDLE sqlenvhandle;
SQLHANDLE sqlconnectionhandle;
SQLHANDLE sqlstatementhandle;
SQLRETURN retcode;
if (SQL_SUCCESS != SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &sqlenvhandle))
goto UNFIN;
if (SQL_SUCCESS != SQLSetEnvAttr(sqlenvhandle, SQL_ATTR_ODBC_VERSION, (SQLPOINTER)SQL_OV_ODBC3, 0))
goto UNFIN;
if (SQL_SUCCESS != SQLAllocHandle(SQL_HANDLE_DBC, sqlenvhandle, &sqlconnectionhandle))
goto UNFIN;
SQLWCHAR retconstring[1024];
cout << "Made it this far at least" << endl;
switch (SQLDriverConnect(sqlconnectionhandle,
NULL,
(SQLWCHAR*)"DRIVER={SQL Server};SERVER=sqlserver.myhost.com, 1433;DATABASE=MyDatabase;UID=xxxxx;PWD=xxxxx",
SQL_NTS,
retconstring,
1024,
NULL,
SQL_DRIVER_NOPROMPT)){
case SQL_SUCCESS_WITH_INFO:
show_error(SQL_HANDLE_DBC, sqlconnectionhandle);
break;
case SQL_INVALID_HANDLE:
case SQL_ERROR:
cout << "Now we're in SQL_ERROR" << endl;
show_error(SQL_HANDLE_DBC, sqlconnectionhandle);
goto FINISHED;
default:
break;
}
if (SQL_SUCCESS != SQLAllocHandle(SQL_HANDLE_STMT, sqlconnectionhandle, &sqlstatementhandle))
goto FINISHED;
if (SQL_SUCCESS != SQLExecDirect(sqlstatementhandle, (SQLWCHAR*)"select * from testtable", SQL_NTS)){
show_error(SQL_HANDLE_STMT, sqlstatementhandle);
goto FINISHED;
}
else{
char name[64];
char address[64];
int id;
while (SQLFetch(sqlstatementhandle) == SQL_SUCCESS){
SQLGetData(sqlstatementhandle, 1, SQL_C_ULONG, &id, 0, NULL);
SQLGetData(sqlstatementhandle, 2, SQL_C_CHAR, name, 64, NULL);
SQLGetData(sqlstatementhandle, 3, SQL_C_CHAR, address, 64, NULL);
cout << id << " " << name << " " << address << endl;
}
}
FINISHED:
SQLFreeHandle(SQL_HANDLE_STMT, sqlstatementhandle);
SQLDisconnect(sqlconnectionhandle);
SQLFreeHandle(SQL_HANDLE_DBC, sqlconnectionhandle);
SQLFreeHandle(SQL_HANDLE_ENV, sqlenvhandle);
goto ALLOVER;
UNFIN:
cout << "Everything is unfinished" << endl;
ALLOVER:
return true;
}
int _tmain(int argc, _TCHAR* argv[])
{
write_to_database();
return 0;
}
EDIT/UPDATE:
Continuing to try and figure out where the error is. Using code based off the tutorial at EasySoft to get the list of DSN available feels a little bit like progress. Here's the updated program and result:
// SQLTest.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include <stdio.h>
#include <string>
#include <iostream>
#include <Windows.h>//Used for sleep command, and window "clearwindow" function
#include <sql.h>
#include <sqltypes.h>
#include <sqlext.h> // Used for writing to SQL database
using namespace std;
static void extract_error(char *fn, SQLHANDLE handle, SQLSMALLINT handletype){
SQLWCHAR sqlstate[1024];
SQLWCHAR message[1024];
if (SQL_SUCCESS == SQLGetDiagRec(handletype, handle, 1, sqlstate, NULL, message, 1024, NULL)){
cout << "Message: ";
wcout << message;
cout << " nSQLSTATE: ";
wcout << sqlstate;
cout << endl;
}
}
static void do_sql(){
SQLHENV env;
SQLWCHAR dsn[256];
SQLWCHAR desc[256];
SQLSMALLINT dsn_ret;
SQLSMALLINT desc_ret;
SQLUSMALLINT direction;
SQLRETURN ret;
SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &env);
SQLSetEnvAttr(env, SQL_ATTR_ODBC_VERSION, (void *)SQL_OV_ODBC3, 0);
direction = SQL_FETCH_FIRST;
cout << "SQL DATA SOURCES:" << endl;
while (SQL_SUCCEEDED(ret = SQLDataSources(env, direction,
dsn, sizeof(dsn), &dsn_ret,
desc, sizeof(desc), &desc_ret))) {
direction = SQL_FETCH_NEXT;
wcout << dsn << " | " << desc << endl;
if (ret == SQL_SUCCESS_WITH_INFO) printf("\tdata truncation\n");
}
SQLHDBC dbc;
SQLHSTMT stmt;
SQLWCHAR outstr[1024];
SQLSMALLINT outstrlen;
/* Allocate an environment handle */
SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &env);
/* We want ODBC 3 support */
SQLSetEnvAttr(env, SQL_ATTR_ODBC_VERSION, (void *)SQL_OV_ODBC3, 0);
/* Allocate a connection handle */
SQLAllocHandle(SQL_HANDLE_DBC, env, &dbc);
/* Connect to the DSN mydsn */
string connstr = "DSN=EnglobalConn";
cout << endl << endl << "ATTEMPTING TO CONNECT TO DATA SOURCE USING:" << endl <<connstr << endl << endl;
ret = SQLDriverConnect(dbc, NULL, (SQLWCHAR*)connstr.c_str(), SQL_NTS,
outstr, sizeof(outstr), &outstrlen,
SQL_DRIVER_NOPROMPT);
if (SQL_SUCCEEDED(ret)) {
printf("Connected\n");
printf("Returned connection string was:\n\t%s\n", outstr);
if (ret == SQL_SUCCESS_WITH_INFO) {
printf("Driver reported the following diagnostics\n");
extract_error("SQLDriverConnect", dbc, SQL_HANDLE_DBC);
}
SQLDisconnect(dbc); /* disconnect from driver */
}
else {
fprintf(stderr, "Failed to connect\n");
extract_error("SQLDriverConnect", dbc, SQL_HANDLE_DBC);
}
/* free up allocated handles */
SQLFreeHandle(SQL_HANDLE_DBC, dbc);
SQLFreeHandle(SQL_HANDLE_ENV, env);
}
int _tmain(int argc, _TCHAR* argv[])
{
do_sql();
return 0;
}
The program gives the following output. Error is the same for both 'EnglobalConn' and 'Englobal2'
SQL DATA SOURCES:
dBASE Files | Microsoft Access dBASE Driver (*dbf, *.ndx, *.mdx)
Excel Files | Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb)
MS Access Database | Microsoft Access Driver (*.mdb, *.accdb)
Englobal2 | SQL Server
EnglobalConn | SQL Server
ATTEMPTING TO CONNECT TO DATA SOURCE USING:
DSN=EnglobalConn
Failed to connect
Message: [Miscrosoft][ODBC Driver Manager] Data source name not found and no default driver specified nSQLSTATE: IM002
One piece of advice I found while Googling was that a 64-bit Windows install has 2 ODBC sets, one in System32 and one in SysWOW64. I've run both and set the DSNs to be the same:
In C:\Windows\SysWOW64\odbcad32.exe:
User Data Sources: Englobal2 - SQL Server
System DSN: EnglobalConn - SQL Server
In C:\Windows\System32\odbcad32.exe:
User Data Sources: Englobal2 - SQL Server
System DSN: EnglobalConn - SQL Server

Answer 1

Hi I've struggled with exactly the same problem and exactly the same fail :)
(SQLWCHAR*)"DRIVER={SQL Server};SERVER=sqlserver.myhost.com, 1433;DATABASE=MyDatabase;UID=xxxxx;PWD=xxxxx",
Should be
(SQLWCHAR*)_T("DRIVER={SQL Server};SERVER=sqlserver.myhost.com, 1433;DATABASE=MyDatabase;UID=xxxxx;PWD=xxxxx"),
or
(SQLWCHAR*)TEXT("DRIVER={SQL Server};SERVER=sqlserver.myhost.com, 1433;DATABASE=MyDatabase;UID=xxxxx;PWD=xxxxx"),

Answer 2

Hooray! Found a solution that works:
Using the library http://otl.sourceforge.net/ (Designed for use with Oracle, but also works to connect to SQL Server):
#include "stdafx.h"
#include <iostream>
using namespace std;
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define OTL_ODBC // Compile OTL 4.0/ODBC
// The following #define is required with MyODBC 3.51.11 and higher
#define OTL_ODBC_SELECT_STM_EXECUTE_BEFORE_DESCRIBE
// #define OTL_ODBC_UNIX // uncomment this line if UnixODBC is used
#include "otlv4.h" // include the OTL 4.0 header file
otl_connect db; // connect object
void insert()
// insert rows into table
{
otl_stream o(1, // buffer size should be == 1 always on INSERT
"insert into test_tab values "
"(:f1<int>, : f2<char[31]>), "
"(:f12<int>, : f22<char[31]>), "
"(:f13<int>, : f23<char[31]>), "
"(:f14<int>, : f24<char[31]>), "
"(:f15<int>, : f25<char[31]>) ",
// INSERT statement. Multiple sets of values can be used
// to work around the lack of the bulk interface
db // connect object
);
// If the number of rows to be inserted is not known in advance,
// another stream with the same INSERT can be opened
otl_stream o2(1, // buffer size should be == 1 always on INSERT
"insert into test_tab values "
"(:f1<int>, : f2<char[31]>)",
db // connect object
);
char tmp[32];
int i;
for (i = 1; i <= 100; ++i){
sprintf_s(tmp, "Name%d", i);
o << i << tmp;
}
for (i = 101; i <= 103; ++i){
sprintf_s(tmp, "Name%d", i);
o2 << i << tmp;
}
}
void update(const int af1)
// insert rows into table
{
otl_stream o(1, // buffer size should be == 1 always on UPDATE
"UPDATE test_tab "
" SET f2 = :f2<char[31]> "
" WHERE f1 = : f1<int>",
// UPDATE statement
db // connect object
);
o << "Name changed" << af1;
o << otl_null() << af1 + 1; // set f2 to NULL
}
void select(const int af1)
{
otl_stream i(50, // buffer size may be > 1
"select :f1<int>, :f2<char[31]> from test_tab "
/*"where f1 >= :f11<int> "*/,
// SELECT statement
db // connect object
);
// create select stream
cout << "Here" <<endl;
int f1;
char f2[31];
i << af1 << af1; // :f11 = af1, :f12 = af1
while (!i.eof()){ // while not end-of-data
i >> f1;
cout << "f1 = " << f1 << ", f2 = ";
i >> f2;
if (i.is_null())
cout << "NULL";
else
cout << f2;
cout << endl;
}
}
int main()
{
otl_connect::otl_initialize(); // initialize ODBC environment
try{
//db.rlogon("root / XX #mysql3532");
db.rlogon("driver={SQL Server};UID=XXXXX;PWD=XXXXXX; server=sqlserver.myserver.com"); // connect to ODBC
// db.rlogon("scott/tiger#mysql35"); // connect to ODBC, alternative format
// of connect string
otl_cursor::direct_exec
(
db,
"drop table test_table",
otl_exception::disabled // disable OTL exceptions
); // drop table
otl_cursor::direct_exec
(
db,
"create table test_table(f1 int, f2 varchar(30))"
//"create table test_tab(f1 int, f2 varchar(30)) type=innoDB" (causes MYSQL error)
); // create table
//insert(); // insert records into the table
//update(10); // update records in the table
//select(8); // select records from the table
otl_cursor::direct_exec(db, "INSERT INTO test_table (f1, f2) VALUES (600,'Test')");
otl_cursor::direct_exec(db, "INSERT INTO test_table (f1, f2) VALUES (-3,'Lest')");
otl_cursor::direct_exec(db, "INSERT INTO test_table (f1, f2) VALUES (4,'Rest')");
otl_cursor::direct_exec(db, "INSERT INTO test_table (f1, f2) VALUES (10,'Best')");
otl_cursor::direct_exec(db, "INSERT INTO test_table (f1, f2) VALUES (19,'Quest')");
//select(20);
}
catch (otl_exception& p){ // intercept OTL exceptions
cerr << "MSG: " << p.msg << endl; // print out error message
cerr << "STM_TEXT: " << p.stm_text << endl; // print out SQL that caused the error
cerr << "SQLSTATE: " << p.sqlstate << endl; // print out SQLSTATE message
cerr << "VAR_INFO: " << p.var_info << endl; // print out the variable that caused the error
}
db.logoff(); // disconnect from ODBC
return 0;
}