自己写的第一个triger

简化前： 

sql 代码

Create Or Replace Trigger tr_cust_order
AFTER  UPDATE
ON te_cust_order
FOR EACH ROW
WHEN (NEW.status=6)
DECLARE
   exhok NUMBER;
   exhid NUMBER;
   regok NUMBER;
   seqexh NUMBER;
   sql_stat varchar2(200);
BEGIN

--判断是否为展览订单
DECLARE
    CURSOR emp_cursor IS
        SELECT service_item_id FROM te_cust_order
    WHERE service_item_id IN
    (SELECT t.id FROM te_cust_service_item t WHERE t.service_type_id IN (2,3,4) );
    emp_record emp_cursor%ROWTYPE;
BEGIN
    OPEN emp_cursor;
    LOOP
        FETCH emp_cursor INTO emp_record;
        exit when emp_cursor%NOTFOUND;
    if emp_record.service_item_id = :old.SERVICE_ITEM_ID then
           exhok := 1;
    end if;
    END LOOP;
    CLOSE emp_cursor;
END;

if exhok != 1 then
return;
end if;

--取得展览ID
exhid := 0;
DECLARE
    CURSOR exh_cursor IS
        SELECT exh_id FROM te_exh_order
    WHERE order_no = :new.order_no;
    exh_record exh_cursor%ROWTYPE;
BEGIN
    OPEN exh_cursor;
    LOOP
        FETCH exh_cursor INTO exh_record;
        exit when exh_cursor%NOTFOUND;
    exhid := exh_record.exh_id ;
    END LOOP;
    CLOSE exh_cursor;
END;

if exhid < 1 then
return;
end if;

--判断是否已经报名了
regok := 0;
SELECT count(*) INTO regok FROM teexhibitiontomember
 WHERE EXHIBITIONID =  exhid and CUSTOMERNO = :new.CUSTOMER_NO;
if regok >0 then
return;
end if;

--增加报名记录
select teexhibitionmemberseq.nextval into seqexh
from teexhibitiontomember t where rownum = 1;

sql_stat := 'insert into teexhibitiontomember(ID,MEMBERID,EXHIBITIONID,CUSTOMERNO) values ('
          || seqexh || ',0,' ||exhid||','''|| :new.CUSTOMER_NO||''')';

execute immediate sql_stat;


END tr_cust_order;

 

简化后：

sql 代码

/*==============================================================*/
/* Trigger： tr_cust_order                               */
/*==============================================================*/

Create Or Replace Trigger tr_cust_order
  AFTER UPDATE ON te_cust_order
  FOR EACH ROW
  WHEN (NEW.status = 6)
DECLARE
  exhid    NUMBER;
  regok    NUMBER;
  seqexh   NUMBER;
  sql_stat varchar2(200);
BEGIN

  --取得展览ID
  SELECT exh_id
    into exhid
    FROM te_exh_order
   WHERE order_no = :new.order_no;

  if exhid < 1 then
    return;
  end if;

  --判断是否已经报名了
  regok := 0;
  SELECT count(*)
    INTO regok
    FROM teexhibitiontomember
   WHERE EXHIBITIONID = exhid
     and CUSTOMERNO = :new.CUSTOMER_NO;
  if regok > 0 then
    return;
  end if;

  --增加报名记录
  select teexhibitionmemberseq.nextval into seqexh from dual;

  sql_stat := 'insert into teexhibitiontomember(ID,MEMBERID,EXHIBITIONID,CUSTOMERNO) values (' ||
              seqexh || ',0,' || exhid || ',''' || :new.CUSTOMER_NO ||
              ''')';

  execute immediate sql_stat;

END tr_cust_order;