쿼리 호출 성능에 관해

BOOL CDBTool::Query(LPCTSTR szQuery, ...)
{
	if(!szQuery) return FALSE;

	CheckReconnect();   // DB 연결이 끊어졌으면 다시 연결 시킨다

	register int	n;
	va_list	        argptr;

	if(!m_szQuery)
	{
		m_szQuery=(LPSTR)calloc(1, MAX_QUERY_ADD_LENGTH);
		if(!m_szQuery) return FALSE;
		m_nQueryLength=MAX_QUERY_ADD_LENGTH;
	}

	va_start(argptr, szQuery);

	while((n=_vsnprintf(m_szQuery, m_nQueryLength-1, szQuery, argptr))<0)
	{
		m_nQueryLength+=MAX_QUERY_ADD_LENGTH;
		m_szQuery=(LPSTR)realloc(m_szQuery, m_nQueryLength);
		if(!m_szQuery)
		{
			va_end(argptr);
			m_szQuery=NULL;
			m_nQueryLength=0;
			return FALSE;
		}
	}

	va_end(argptr);

	m_szQuery[n]=0;

	if(m_hStmt!=NULL)
	{
		SQLFreeHandle(SQL_HANDLE_STMT,m_hStmt);
		//SQLFreeStmt(m_hStmt, SQL_DROP);
		m_nErrorNo=SQLAllocHandle(SQL_HANDLE_STMT,m_hDBC,&m_hStmt);
		//SQLAllocStmt(m_hDBC, &m_hStmt);
	}
	else
	{ 
		m_nErrorNo=SQLAllocHandle(SQL_HANDLE_STMT,m_hDBC,&m_hStmt);
		//m_nErrorNo=SQLAllocStmt(m_hDBC, &m_hStmt);
	}

	// 일정한 시간이 지날때까지 쿼리가 풀리지 않으면 해당 쿼리를 무시하고 루틴을 빠져나가게 셋팅한다.
	SQLSetStmtAttr(m_hStmt,SQL_ATTR_QUERY_TIMEOUT,(void*)m_LongQueryWaitTime,SQL_IS_UINTEGER);

	time_t start_time,elsp_time;   // 시작 시간과 지난시간을 가져온다.

	time(&start_time);

	m_nErrorNo=SQLExecDirect(m_hStmt, (SQLCHAR*)m_szQuery, SQL_NTS);

	time(&elsp_time);

	if ( (elsp_time - start_time) >= m_LongQueryLogTime )    // 쿼리가 지정한 시간 이상으로 오래 걸리면
	{
#ifdef _DEBUG
		MessageBox(NULL,"timeover warnning.","SQL TIME",MB_OK);
#endif

		FILE * f;
		char datebuf[20],timebuf[20] ;

		_strdate(datebuf);
		_strtime(timebuf);

		f = fopen("query_timeover.log","a");
		fprintf(f,"%s %s %d | %s \n",datebuf,timebuf,elsp_time - start_time,m_szQuery);
		fclose(f);
	}

	if(m_nErrorNo!=SQL_SUCCESS && m_nErrorNo!=SQL_SUCCESS_WITH_INFO) 
	{
		FILE * f;
		static char btz=0;
		char datebuf[20],timebuf[20] ;

		if (!btz)
		{
			_tzset();
			btz = 1;
		}

		_strdate(datebuf);
		_strtime(timebuf);

		_TUCHAR* szErrorMsg;
		_TUCHAR* pSqlState;
		SDWORD	NativeError;
		SWORD	svErrorMsg;

		szErrorMsg = new _TUCHAR[ SQL_MAX_MESSAGE_LENGTH-1];
		pSqlState = new _TUCHAR[SQL_MAX_MESSAGE_LENGTH-1];

		SQLError(m_hEnv, m_hDBC, m_hStmt, pSqlState, &NativeError, szErrorMsg, SQL_MAX_MESSAGE_LENGTH-1, &svErrorMsg);

#ifdef _DEBUG
		MessageBox(NULL,(char*)szErrorMsg,"SQL ERROR",MB_OK);
#endif

		f = fopen(m_szFileName,"a");
		fprintf(f,"%s %s %s %s \n",datebuf,timebuf,pSqlState,m_szQuery);
		fclose(f);

		// Connection does not exist.
		if (memcmp(pSqlState,"08003",5)==0)
		{
			m_isConn = FALSE;
		}
		// Communication link failure. The communication link between the driver and the data source 
		// to which the driver was connected failed before the function completed processing. 
		else if (memcmp(pSqlState,"08S01",5)==0)
		{
			m_isConn = FALSE;
		}

		// SQL 상태코드들이 들어 있습니다.
		delete pSqlState;
		delete szErrorMsg;
		return FALSE;
	}

	return	TRUE;
}