CREATE TRIGGER CHANGE_STORY FOR SYSTEM_BLOCK
ACTIVE BEFORE INSERT or  UPDATE or DELETE POSITION 0
AS
declare variable id_ integer;
declare variable time_ timestamp;
declare variable op_ char(20);
declare variable oldprice numeric(16, 2);
declare variable newprice numeric(16, 2);
BEGIN
  id_=GEN_ID(GENA_TRIG, 1);
  if(inserting)
  begin
     op_='Добавление';
     time_=current_timestamp;
     oldprice=0;
     newprice=NEW.block_price;
  end
if(updating)
  begin
     op_='Обновление';
     time_=current_timestamp;
     oldprice=OLD.block_price;
     newprice=NEW.block_price;
  end
  INSERT INTO supersecrettable(ID, TI_ME, OPERATION, OLD_RICE, NEW_PRICE) values
  (:id_, :time_,  :op_, :oldprice, :newprice);

END