--- In firebird-support@yahoogroups.com, "heroes3lover"
<heroes3lover@...> wrote:

>
> --- In firebird-support@yahoogroups.com, "heroes3lover"
> <heroes3lover@> wrote:
> >
> > Hello everyone,
> > I got a problem.
> > Because some SQL is huge and make program no response for a

while,

> we
> > have to use thread to retrieve data, below is my
> > code,TSQLCompleteDataSetPlus is a component we inherited from
> > TSQLCompleteDataSet(this is component of dbexpressplus),
> > but when the process running to qryInThread.open, sometimes the
> whole
> > program jammed, and looks like die, and cpu usage is 0%, I think
> > should be something wrong with thread safe issue, but I can not
> find
> > out, cauz all stuff I created them in thread.
> > Is there anybody can figure out the possible issue?
> > Thanks very much
> > Roc
> >
> >
> > TDataThread = class( TThread )
> > qryInThread : TSQLQuery;
> > conInThread : TSQLConnection;
> > Log : TProcessLogger;
> > isSelect : Boolean;
> > constructor Create;
> > destructor Destory;
> > procedure WriteStartLog;
> > procedure WriteEndLog;
> > procedure WriteError;
> > end;
> >
> > TSQLCompleteDataSetPlusThread = class( TDataThread )
> > public
> > constructor Create( SQLQuery : TSQLCompleteDataSetPlus );
> > procedure Execute; override;
> > end;
> >
> > { TSQLThread }
> >
> > constructor TDataThread.Create;
> > begin
> > inherited Create(TRUE);
> > FreeOnTerminate := FALSE;
> > qryInThread := TSQLQuery.Create(nil);
> > conInThread := TSQLConnection.Create(nil);
> > Log := TProcessLogger.Create;
> > conInThread.SQLHourGlass := False;
> > isSelect := True;
> > end;
> >
> > destructor TDataThread.Destory;
> > begin
> > qryInThread.Close;
> > conInThread.Connected := False;
> > while( conInThread.ConnectionState <> csStateClosed ) do;
> > FreeAndNil(qryInThread);
> > FreeAndNil(conInThread);
> > FreeAndNil(Log);
> > end;
> >
> >
> > procedure TDataThread.WriteEndLog;
> > begin
> > Log.EndLog;
> > end;
> >
> > procedure TDataThread.WriteStartLog;
> > var
> > TheMsg : String;
> > begin
> > case qryInThread.SQLConnection.ConnectionState of
> > csStateClosed:TheMsg := 'close';
> > csStateOpen:TheMsg := 'open';
> > csStateConnecting:TheMsg := 'connecting';
> > csStateExecuting:TheMsg := 'executing';
> > csStateFetching:TheMsg := 'fetching';
> > csStateDisconnecting:TheMsg := 'disconnecting';
> > End;
> > Log.StartLog(TheMsg);
> > end;
> >
> > procedure TDataThread.WriteError;
> > begin
> > LogErrorMessage('Thread Error');
> > end;
> >
> > constructor TSQLCompleteDataSetPlusThread.Create(SQLQuery:
> > TSQLCompleteDataSetPlus);
> > var
> > Backup : TSQLConnection;
> > begin
> > inherited Create;
> > Backup := SQLQuery.SQLConnectionPlus;
> > conInThread.DriverName := Backup.DriverName;
> > //set conInThread parameters
> > conInThread.LoginPrompt := False;
> > conInThread.Connected := True;
> > qryInThread.Close;
> > qryInThread.SQLConnection := conInThread;
> > qryInThread.SQL.Assign(SQLQuery.SQL);
> > qryInThread.Params.AssignValues(SQLQuery.Params);
> > end;
> >
> > procedure TSQLCompleteDataSetPlusThread.Execute;
> > begin
> > Try
> > Synchronize(WriteStartLog);
> > if isSelect then
> > qryInThread.Open;
> > else
> > qryInThread.ExecSQL;
> > Synchronize(WriteEndLog);
> > Except
> > on e:exception do
> > Synchronize(WriteError);
> > end;
> > Terminate;
> > end;
> >
>
>
> And there is no error or exception in firebird.log or the program,
> looks like nothing happen, just the cpu 0% and program no response.
> It's very annoying.
> Does anybody have any idea???
>
> Thanks,
> Roc
>

Finally find it's a mistake of mine,
in some situations we use local connection.
sign....

Roc