--- 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