Hi,
I just tested that same code under Windows 2000 and I don't have any
errors or duplicates. As I would have expected. So there seems to be
a bug in the CreateGUID implementation of Linux.
BTW:
I'm using Ubuntu 7.10. My 'uname -a' output:
Linux graemeg 2.6.22-14-generic #1 SMP Tue Feb 12 07:42:25 UTC 2008
i686 GNU/Linux
Regards,
- Graeme -
On 29/05/2008, Graeme Geldenhuys <[EMAIL PROTECTED]> wrote:
> Hi,
>
> I'm trying to do performance testing in Firebird RDBMS using GUID's
> and primary keys. I constantly got PK violations. I then wrote the
> code show below to create 50,000 GUID's and add them to a StringList
> (no duplicates allowed). Every time I run this I get a duplicate GUID
> at iteration 1021. My original test is supposed to create 5mil
> records, but I can't get past 1000! :-(
>
> Actual program output:
>
> [EMAIL PROTECTED]:index_performance$ ./index_performance.elf
> Duplicate value detected: {FD3DF19D-A878-F8BA-F9D1-108658451E05}
> List.Count = 1021
>
> GUID's are supposed to be very unique! Wikipedia says something like:
> Create a billion every second for 10 years or something before you
> deplete the range.
> So what is wrong with my code or maybe the Free Pascal implementation?
>
> --------------------[ code ]------------------------------
> procedure TMainForm.btnTestClicked(Sender: TObject);
> var
> sl: TStringList;
> s: string;
> i: integer;
> d: integer;
> guid: TGUID;
> begin
> sl := TStringList.Create;
> try
> try
> sl.Sorted := True;
> sl.Duplicates := dupError;
> for i := 1 to 50000 do
> begin
> CreateGUID(guid);
> s := GUIDToString(guid);
> sl.Add(s);
> end;
> writeln('Created 50,000 GUIDs');
> except
> on e: EStringListError do
> begin
> writeln('Duplicate value detected: ' + s);
> writeln(' List.Count = ', sl.Count);
> end;
> on e: Exception do
> writeln('Unknown error: ', e.Message);
> end;
> finally
> sl.Free;
> end;
> end;
> --------------------[ end ]--------------------------------
>
>
> Changing the line that adds the GUID to the StringList by prefixing
> the counter, all is fine. So I can't see a problem in my code.
>
> sl.Add(IntToStr(i) + s);
>
>
> Regards,
> - Graeme -
>
>
> _______________________________________________
> fpGUI - a cross-platform Free Pascal GUI toolkit
> http://opensoft.homeip.net/fpgui/
>
--
Regards,
- Graeme -
_______________________________________________
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http://opensoft.homeip.net/fpgui/
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