hello unknown(?),

you have not specified if you are using native TIB_... components or dataset
based TIBO... ones.

Anyway, if you are using native components such as TIB_Query, the simpliest
way to achieve what you are doing is to define a simple prompt message in
the ConfirmDeletePrompt property, otherwise write a BeforeDelete handler:

MyForm.MyQueryBeforeDelete(IB_Dataset: TIB_Dataset);

begin
if MessageDlg('Do you really want to delete this row?', mtConfirmation,
[mbYes, mbNo], 0) <> mrYes then
Abort
end;

Regards
Salvatore