create table test (p_c varchar2(30));create trigger a_row_tri
before delete on A
for each row
begin
insert into test values(:old.C);
end;
/
create trigger a_tri
after delete on a
begin
update 表A set 表A.列B = Null where 表A.列B in (select p_c from test);
delete from test;
end;
/
before delete on A
for each row
begin
insert into test values(:old.C);
end;
/
create trigger a_tri
after delete on a
begin
update 表A set 表A.列B = Null where 表A.列B in (select p_c from test);
delete from test;
end;
/
after delete on 表A for each row
declare ss char(30);begin
ss:=:old.列C;
update 表A set 表A.列B = Null where 表A.列B = ss;
end
但是用了临时表,是否有其他更好的解决办法?