Datenbank für schnelle Bilder, Vorschläge bitte.

[KodeZwerg]

Die Suche ist Aufgebaut nach diesem Beispiel-Code von UIB:

Delphi-Quellcode:

unit main;

interface

uses
{$IFDEF LINUX}
  libc, QForms, QStdCtrls, QControls, QGraphics, QDialogs, QExtCtrls,
{$ELSE}
  Windows, Graphics, Controls, Forms, Messages, Dialogs, StdCtrls,
{$ENDIF}
  SysUtils, Classes, uib, SyncObjs;

type
  TForm1 = class(TForm)
    DataBase: TUIBDataBase;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Déclarations privées }
  public
    { Déclarations publiques }
  end;

  TMyThread = class(TThread)
  protected
    procedure Execute; override;
    destructor destroy; override;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  i: integer;
begin
  for i := 0 to 49 do
    TMyThread.Create(False);
end;

var
  x: integer = 0;

{ TMyThread }

destructor TMyThread.destroy;
begin
  inherited;
end;

procedure TMyThread.Execute;
var
  Query: TUIBQuery;
  Transaction: TUIBTransaction;
begin
  FreeOnTerminate := true;
  // Form1.DataBase.Lock; //simulate single thread
  try
    Query := TUIBQuery.Create(nil);
    Transaction := TUIBTransaction.Create(nil);
    try
      Transaction.DataBase := Form1.DataBase;
      Query.Transaction := Transaction;
      Query.FetchBlobs := True;
      Query.SQL.Text := 'select * from project';
      Query.Open;
      while not Query.EOF do
      begin
        Query.Next;
        Sleep(10); // simulate activity
      end;
    finally
      Query.Close(etmCommit);
      Query.Free;
      Transaction.Free;
    end;
  finally
    // Form1.DataBase.UnLock; //simulate single thread
  end;
end;

end.

Die Bilder hole ich mir wie in diesem UIB-Code Sample:

Delphi-Quellcode:

unit main;

interface

uses
{$IFDEF LINUX}
  libc, QForms, QStdCtrls, QControls, QGraphics, QDialogs, QExtCtrls,
{$ELSE}
  Windows, Graphics, Controls, Forms, Messages, Dialogs, StdCtrls, ExtCtrls,
{$ENDIF}
  SysUtils, Classes, uib;

type
  TMainForm = class(TForm)
    Image: TImage;
    LoadImage: TButton;
    SaveImage: TButton;
    DataBase: TUIBDataBase;
    Transaction: TUIBTransaction;
    Query: TUIBQuery;
    OpenDialog: TOpenDialog;
    procedure LoadImageClick(Sender: TObject);
    procedure SaveImageClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  MainForm: TMainForm;

implementation

uses Math;

{$R *.dfm}

procedure TMainForm.LoadImageClick(Sender: TObject);
var
  Stream: TMemoryStream;
begin
  Query.SQL.Text := 'Select Stream from TBLOB';
  Query.Params.Clear;
  Query.Open;
  Stream := TMemoryStream.Create;
  try
    Query.ReadBlob('STREAM', Stream);
    Image.Picture.Bitmap.LoadFromStream(Stream);
  finally
    Stream.Free;
  end;
  Query.Close(etmCommit);
end;

procedure TMainForm.SaveImageClick(Sender: TObject);
var Stream: TFileStream;
begin
  If OpenDialog.Execute then
  begin
    Stream := TFileStream.Create(OpenDialog.FileName, fmOpenRead);
    try
      Query.SQL.Text := 'UPDATE TBLOB SET STREAM = :blob';
      Query.ParamsSetBlob('blob', Stream);
      Query.ExecSQL;
    finally
      Stream.Free;
    end;
    Query.Close(etmCommit);
  end;
end;

end.