I notice that KeyLinksAutoDefine = False, but that there's still not defined any KeyLinks. I'm not certain, but it wouldn't surprise me if IBO didn't use RDB$DB_KEY when KeyLinksAutoDefine = false. IBO must somehow be able to uniquely identify a record, it cannot automagically delete the current record without knowing how to separate it from other records, and RDB$DB_KEY is the "magic" that is normally used if there's no other fields that are unique (though it should only be used within the same transaction).

HTH,

Set

man. 25. mar. 2019 kl. 23:59 skrev jackmason@... [IBObjects] <IBObjects@yahoogroups.com>:

This program simply starts deleting records from the front of a table.  However, it gets intermittent errors saying it cannot find the row to delete even though there may be hundreds of rows left in the table.  The table does not have a primary key. 

The code contains a comment section showing the DDL for the table and a button to put 4 rows into the table.  If you start with an empty table and put 4 rows into the table, then click the 'Go' button, the failure likely will occur trying to delete the first row..  If you close the program after adding the 4 rows, restart the program and click 'Go', it will usually correctly delete all 4 rows.  With many rows in the table, it will delete some rows and then get the error. 

I have tried using a refresh after each delete, but it still fails.

I am using ibo5_10_1_b2808_Source and Embarcadero 10.3 Studio. 

[code]

unit Delete;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, IB_Components, IB_Access, IBODataset,
  Data.DB, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    Query2: TIBOQuery;
    DB: TIBODatabase;
    Button2: TButton;
    Query: TIBOQuery;
    QueryNUMBER: TIntegerField;
    QueryENTERED: TDateTimeField;

    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);

  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
{   DDL for table 'Stuff'

CREATE TABLE Stuff

(
  NUMBER          INTEGER           NOT NULL,
  ENTERED         TIMESTAMP         NOT NULL
);
}

procedure TForm1.Button2Click(Sender: TObject);
var Idx: integer;
    TS: TDateTime;
begin
  Query.Filtered := false;
  Query.Open;
  for Idx := 1 to 3 do
    begin
      Query..Append;
      QueryNUMBER.Value := Idx;
      QueryENTERED.Value := Now;
      Query.Post;
    end;
//  Duplicate record
  TS := QueryENTERED.Value;
  Query.Append;
  QueryNUMBER.Value := 3;
  QueryENTERED.Value := TS;
  Query.Post;
  ShowMessage('Added 4 rows to table.');
end;

procedure TForm1.Button1Click(Sender: TObject);
var Last_Number: integer;
begin
  Query.First;
  Last_Number := 0;
  while not Query.Eof do
    begin
      if QueryNUMBER.Value = Last_Number then
        begin
          ShowMessage('Deleting Duplicate #' + QueryNUMBER.AsString);
          Query.Delete;
          continue;
        end;
      ShowMessage('Deleting # ' + QueryNumber..AsString);
      Query.Delete;
    end;

end;

end.

[/code]