16 PL/SQL DML触发器

create or replace trigger trig1
after insert on scott.test
begin
  dbms_output.put_line('添加成功...');
end;

create or replace trigger trig2
after update on scott.test
for each row/*行触发,默认是表触发*/
begin
  dbms_output.put_line('修改成功...');
end;

create or replace trigger trig3
before delete on scott.test
begin
  if to_char(sysdate,'day') in ('星期五','星期六') then
  dbms_output.put_line('删除成功...');
  end if;
end;

create or replace trigger trig4
before insert or update or delete on scott.test
begin
  case
    when inserting then
      dbms_output.put_line('请不要添加...');
    when updating then
      dbms_output.put_line('请不要修改...');
    when deleting then
      dbms_output.put_line('请不要删除...');
  end case;
end;