Question

I am testing out Absolute Database by ComponentAce

I have on my Form a TABSTable, TABSDatabase and a TDataSource and the data is being displayed in a TDBAdvListView, MultiSelect and RowSelect are True. I have only one Table.

When either one or more of the Items in the TDBAdvListView are selected I want to have the Database Delete the selected Records.

I have tried this way in the code below:

procedure TMain.DeleteEntry2Click(Sender: TObject);
var
  i: Integer;
begin
  with DBAdvListView1.DataSource.DataSet do
  begin
    for i := DBAdvListView1.Items.Count - 1 downto 0 do begin
    if DBAdvListView1.Items[i].Selected then
    begin
      DBAdvListView1.DataSource.DataSet.GotoBookmark(Pointer(DBAdvListView1.Items[i]));
      DBAdvListView1.DataSource.DataSet.Delete;
      end;
    end;
  end;
end;

This always results in an Error Message:

Cannot retrieve record - Native error: 10026

I have very little experience with database programming, what am I doing wrong?

Edit:

I have added a new field into the database named ID as an integer starting from 0 in the hopes that I can reference them with the Locate method and tried with the code below. This produces no error but will only delete the top record in the ListView and if I select more than one it will delete different records than selected.

My new code:

procedure TMain.DeleteEntry2Click(Sender: TObject);
var
  i: Integer;
begin
  with DBAdvListView1.DataSource.DataSet do
  begin
    DBAdvListView1.BeginUpdate;
    First;
    for i := DBAdvListView1.Items.Count - 1 downto 0 do begin
    if DBAdvListView1.Items[i].Selected then
    begin
      if dbTable.Locate('ID',DBAdvListView1.Items[i].Selected,[]) then
      dbTable.Delete;
      Next;
      end;
    end;
  dbTable.Close;
  dbTable.Open;
  DBAdvListView1.EndUpdate;
  end;
end;

The dbTable has to be Closed and Opened to see changes for some strange reason – I have tried Refresh to no avail…

Edit:

// To include Table Structure as requested…

• ID integer 0
• Title string 200
• Author string 100
• Date string 20
• Location string 60
• Category string 100
• ISBN-13 string 20
• ISBN-10 string 20

In the Absolute Database Utils directory there is a DatabaseManager.exe which I used to create the actual table with and in here I have also now set a Primary Key of the type:

Type – Primary
Name – ID

The fields for the Index:

ColumnName – ID
CaseInsensitive – False
ASC – True
MaxIndexSize – 20

Answer 1

Answer to own question… I remove the selected records with the code below:

procedure TMain.Button5Click(Sender: TObject);
var
  i: Integer;
begin
  with DBAdvListView1 do
    for i := 0 to Items.Count - 1 do
      if Items[i].Selected then
      begin
        Memo1.Lines.Add(Items[i].Caption + ' - Selected!'); //Test for Correct ID's!
      if dbTable.Locate('ID', Items[i].Caption, []) then
      DBAdvListView1.Datasource.DataSet.Delete;
    end;
  dbTable.Close;
  dbTable.Open;
end;