Delphi-PRAXiS - Delphi Zeos Query - too many connections

Also hier mal zur Erklaerung, vielleicht kann man den Fehler so finden:

Habe 2 Units Model.pas und Model_Database.pas

In Model.pas habe ich folgende Klassen:

Delphi-Quellcode:

			
  TAttributes = class(TObject)

  private

  public

  end;

  TMain = class(TObject)

  private

  public

    function DBSearch(Criteria: TAttributes): TObjectList; Virtual; Abstract;

    function DBCreate(): TZQuery; Virtual; Abstract;

    function DBEdit(): TZQuery; Virtual; Abstract;

    function DBDelete(): TZQuery; Virtual; Abstract;

  end;

  { ---- Attributes ---- }

  TDockingstationAttributes = class(TAttributes)

  private

    FComment: String;

    FFabricant: String;

    FID: Integer;

    //..

  public

    function GetComment: String;

    function GetFabricant: String;

    function GetID: Integer;

   //...

    procedure SetComment(Comment: String);

    procedure SetFabricant(Fabricant: String);

    procedure SetID(ID: Integer);

    //...

  end;

  { ---- /Attributes ---- }

  { ---- Main ---- }

  TDockingstation = class(TMain)

  private

    FAttributes : TDockingstationAttributes;

  public

    constructor Create();

    function GetAttributes(): TDockingstationAttributes;

    procedure SetAttributes(Comment: String='';Fabricant: String='';

      ID: Integer=0; ...);

  end;

  { ---- /Main ---- }

  { ---- Search ---- }

  TDockingstationSearch = class(TMain)

  private

  public

    function DBSearch(Modus: String; Criteria: TDockingstationAttributes)

      : TObjectList; Overload;

  end;

  { ---- /Search ---- }

  { ---- Attributes ---- }

  TComputerAttributes = class(TAttributes)

  private

    //..

    FComment: String;

    //..

    FGraphicCard: String;

  //..

    FDockingstation: TDockingstation; // <-- Computer enthaelt dockingstation objekt

  public

  //..get/set

  end;

  { ---- /Attributes ---- }

  { ---- Main ---- }

  TComputer = class(TMain)

  private

    FAttributes: TComputerAttributes;

  public

    constructor Create();

    function GetAttributes(): TComputerAttributes;

    procedure SetAttributes(Comment: String='';...GraphicCard: String='';...);

  end;

  { ---- /Main ---- }

  { ---- Search ---- }

  TComputerSearch = class(TMain)

  private

  public

    function DBSearch(Modus: String; Criteria: TComputerAttributes): TObjectList; Overload;

  end;

  { ---- /Search ---- }

implementation

//............

function TDockingstationSearch.DBSearch(Modus: String;

  Criteria: TDockingstationAttributes): TObjectList;

var

FMdbDsSearch: Model_Database.TDockingstationSearch;

FWsList: TObjectList;

begin

  FWsList := TObjectList.Create;

  FMdbDsSearch := Model_Database.TDockingstationSearch.Create;

  FWsList := FMdbDsSearch.DBSearch(Modus,Criteria);

  Result := FWsList;

end;

//................

function TComputerSearch.DBSearch(Modus: String; Criteria: TComputerAttributes)

  : TObjectList;

var

FMdbCSearch: Model_Database.TComputerSearch;

FCList: TObjectList;

begin

  FCList := TObjectList.Create;

  FMdbCSearch := Model_Database.TComputerSearch.Create;

  FCList := FMdbCSearch.DBSearch(Modus,Criteria);

  Result := FCList;

end;

//..

In Model_Database.pas steht folgendes:

Delphi-Quellcode:

			  TDatabase = class(TObject)

  private

    FWQuery : TZQuery;

    FDQuery : TZQuery;

    FCQuery : TZQuery;

    FMQuery : TZQuery;

    FSqlConnection : TZConnection;

  public

    constructor Create();

    function DBSearch(Criteria: Model.TAttributes)

      : TObjectList; virtual; abstract;

    procedure DBCreate(); virtual; abstract;

    procedure DBEdit(); virtual; abstract;

    procedure DBDelete(); virtual; abstract;

  end;

  TDockingstationSearch = class(TDatabase)

  private

  public

    function DBSearch(Modus: String; Criteria: Model.TDockingstationAttributes)

      : TObjectList; Overload;

  end;

  TComputerSearch = class(TDatabase)

  private

  public

    function DBSearch(Modus: String; Criteria: Model.TComputerAttributes)

      : TObjectList; Overload;

  end;

implementation

constructor TDatabase.Create();

begin

  FSqlConnection := TZConnection.Create(FSqlConnection);

  FSqlConnection.HostName := '';  //Server

  FSqlConnection.User := '';  //Benutzername

  FSqlConnection.Password := '';  //Passwort

  FSqlConnection.Database := '';  //Name der Datenbank

  FSqlConnection.Protocol := 'mysql-4.1';

  FSqlConnection.Port := 3306;

  FDQuery := TZQuery.Create(FDQuery);

  FDQuery.Connection := FSqlConnection;

  FCQuery := TZQuery.Create(FCQuery);

  FCQuery.Connection := FSqlConnection;

end;

function TDockingstationSearch.DBSearch(Modus: String;

  Criteria: Model.TDockingstationAttributes): TObjectList;

var

FDSList: TObjectList;

I: Integer;

FEqual1,FEqual2 : String;

FMyDockingstation: Model.TDockingstation;

begin

  FDSList := TObjectList.Create;

  FMyDockingstation := Model.TDockingstation.Create;

//...

  // Search in the database for dockingstations by using the criteria

  FDQuery.Close;

  FDQuery.SQL.Text := 'SELECT * FROM Dockingstation';

  FDQuery.SQL.Add(' WHERE (1=1');

//...

  FDQuery.SQL.Add(')');

  FDQuery.Open;

  while not FDQuery.EOF do

  begin

    // Use search result to create a new dockingstation object

    FMyDockingstation.SetAttributes('','',

      FDQuery.FieldByName('DockingstationID').AsInteger,'',

       );

    // Add dockingstation to a list of dockingstation ojects

    FDSList.Add(FMyDockingstation);

    FDQuery.Next;

  end;

  FDQuery.Free;

  Result := FDSList;

end;

function TComputerSearch.DBSearch(Modus: String;

  Criteria: Model.TComputerAttributes): TObjectList;

var

//..

begin

  //..

  FCList := TObjectList.Create;

//..

  // Search in the database for computers by using the criteria

  FCQuery.Close;

  FCQuery.SQL.Text := 'SELECT';

  FCQuery.SQL.Add('....');

//...

  FCQuery.Open;

  while not FCQuery.EOF do

  begin

    FMyComputer := Model.TComputer.Create;

    // Use search result to create a new computer object

    FMyID := FCQuery.FieldByName('RechnerID').AsInteger;

    FMyComment := FCQuery.FieldByName('Bemerkungen').AsString;

    FMyGraphicCard := FCQuery.FieldByName('Grafikkarte').AsString;

    //...

// HIER KOENNTE DER FEHLER LIEGEN WEIL ICH HIER WIEDER EINE DOCKINGSTATIONSEARCH ERZEUGE UND DAS GANZE IN DER GROSSEN WHILE SCHLEIFE VOM FCSQLQUERY ---------------------

  if (FCQuery.FieldByName('DockingstationID').AsInteger > 0) then

      begin

        FMyDSearch := TDockingstationSearch.Create;

        FMyDCriteria := TDockingstationAttributes.Create;

        // Search for the dockingstation that is used by the computer

        FMyDCriteria.SetID(

          FCQuery.FieldByName('DockingstationID').AsInteger);

        FDList := FMyDSearch.DBSearch('vague',FMyDCriteria);

        // Create the dockingstation object for the computer object

        FMyDockingstation := FDList[0] as Model.TDockingstation;

      end;

//---------------------

    // Set all the information of the computer object

    FMyComputer.SetAttributes(...,FMyComment,...,FMyGraphicCard,.., FMyDockingstation...);

    // Add computer object to a list of computer ojects

    FCList.Add(FMyComputer);

    FCQuery.Next;

  end;

  FCQuery.Free;

  Result := FCList;

end;