Trigger to copy row before delete

[kamil kamil]

Hey,

I have a problem with trigger copying deleted row.

Original table: documents
Backup table: documents_backup

Table documents_backup has got 3 extra columns:

- id_pk (primary key)
- timestamp
- operation_type ('delete')

My trigger looks like this:

drop trigger if documents_deletetrigger;
DELIMITER
create trigger documents_deletetrigger
before delete on documents
for each row
begin

insert into values (NULL, CURRENT_TIMESTAMP, "delete", (select * from `documents` where id=old.id));

end;

While I'm trying to delete row from table `documents` i have an error:

'Operand should contain 1 column'

I'll be grateful for any clues. :)