create table tab1 (id number, dd date, vv varchar2(32))
/
create table log_tab1 (id number, ld date, la varchar2(1), lm varchar2(100), vv_old varchar2(32), vv_new varchar2(32))
/
create sequence log_tab1_seq
/
create or replace trigger tr_tab1_u
	for update of dd, vv on tab1
	compound trigger  
  l_cnt number := 0;
	-- AFTER EACH ROW Section:
	after each row is
	begin
		l_cnt := l_cnt + 1;
		--if l_cnt > 3 then
		--	raise_application_error(-20001, 'Нельзя одновременно обновлять столько строк!');
		--end if;
    insert into log_tab1(id, ld, la, lm, vv_old, vv_new)
    values (log_tab1_seq.nextval, :new.dd, 'u', 'обновление записи id =' ||to_char(:new.id)||' l_cnt = '||to_char(l_cnt), :old.vv, :new.vv);
	end after each row;
end;
/
create or replace trigger tr_tab1_d
	for delete on tab1
	compound trigger  l_cnt number := 0;
	-- AFTER EACH ROW Section:
	after each row is
	begin
		l_cnt := l_cnt + 1;
		--if l_cnt > 3 then
		--  raise_application_error(-20001, 'Нельзя одновременно обновлять столько строк!');
		--end if;
		insert into log_tab1
			(id, ld, la, lm, vv_old, vv_new)
		values
			(log_tab1_seq.nextval, :old.dd, 'd', 'удаление записи id =' || to_char(:new.id), :old.vv, null);
	end after each row;
end;
/
insert into tab1
	select level, sysdate, to_char(level) from dual connect by rownum <= 4
/  
merge into tab1 t using (
    select 1 i,'u' o from dual union all
    select 2 i,'u' o from dual union all
    select 3 i,'d' o from dual union all
    select 4 i,'d' o from dual union all
    select 5 i,'i' o from dual union all
    select 6 i,'i' o from dual
    ) m
on (t.id=m.i)
WHEN MATCHED THEN UPDATE SET t.vv = m.o
   DELETE WHERE (t.vv='d')
WHEN NOT MATCHED THEN INSERT (id,vv) values (m.i,m.o)
/
select * from log_tab1 order by id
/

Table created
Table created
Sequence created
Trigger created
Trigger created
4 rows inserted
6 rows merged
        ID LD          LA LM                                                                               VV_OLD                           VV_NEW
---------- ----------- -- -------------------------------------------------------------------------------- -------------------------------- --------------------------------
         1 15.08.2016  u  обновление записи id =1 l_cnt = 1                                                1                                u
         2 15.08.2016  u  обновление записи id =2 l_cnt = 2                                                2                                u
         3 15.08.2016  u  обновление записи id =3 l_cnt = 3                                                3                                d
         4 15.08.2016  d  удаление записи id =                                                             d                                
         5 15.08.2016  u  обновление записи id =4 l_cnt = 4                                                4                                d
         6 15.08.2016  d  удаление записи id =                                                             d                                
6 rows selected