给了你数据库和程序的源代码怎么建立连接(数据库为SQL)

抄一段使用ODBC API连接的代码:
#include <windows.h>
#include "stdio.h"
#include<sql.h>
#include<sqlext.h>
#include<sqltypes.h>
#include<odbcss.h>

int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
SQLHENV m_hEnv;
SQLHDBC m_hDbc;
SQLRETURN m_sr;
m_sr=SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&m_hEnv);
if(m_sr!=SQL_SUCCESS)
{ MessageBox(NULL,"分配环境句柄失败","错误",MB_OK|MB_ICONEXCLAMATION);

return FALSE;
}
m_sr=SQLSetEnvAttr(m_hEnv,SQL_ATTR_ODBC_VERSION,(SQLPOINTER)SQL_OV_ODBC3,0);
if(m_sr!=SQL_SUCCESS)
{ MessageBox(NULL,"设置环境属性失败","错误",MB_OK|MB_ICONEXCLAMATION);

return FALSE;
}
m_sr=SQLAllocHandle(SQL_HANDLE_DBC,m_hEnv,&m_hDbc);
if(m_sr!=SQL_SUCCESS)
{ MessageBox(NULL,"分配连接句柄失败","错