⤷ Clear all records of field

You may use Clear method for all records of specified field. For manipulating of records use First, Edit, Post and Next methods.

procedure TForm1.Button1Click(Sender: TObject);
begin
  with Table1 do
  begin
    First;
    while not EOF do
    begin
      Edit;
      FieldByName('SIZE').Clear;
      Post;
      Next;
    end;
  end;
end;
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