假如A表中有一些欄位,B表為空表,當A表update時,將update的內容放在B表內以供使用
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主要是觸發器怎么寫uj5u.com熱心網友回復:
-- 給你寫個例子
SQL>
SQL> create table ta(id int, name varchar(10), age int);
Table created
SQL> create table tb(id int, old_name varchar(10), new_name varchar(10));
Table created
SQL> create trigger tri_ta_update
2 before update on ta
3 for each row
4 begin
5 insert into tb(id, old_name, new_name)
6 values(:new.id, :old.name, :new.name);
7 end;
8 /
Trigger created
SQL> begin
2 insert into ta values(100, 'zs', 100);
3 update ta set name = 'abc';
4 update ta set name = 'zxy';
5 end;
6 /
PL/SQL procedure successfully completed
SQL> col id format a5;
SQL> select * from ta;
ID NAME AGE
----- ---------- ---------------------------------------
100 zxy 100
SQL> select * from tb;
ID OLD_NAME NEW_NAME
----- ---------- ----------
100 zs abc
100 abc zxy
SQL> drop table ta purge;
Table dropped
SQL> drop table tb purge;
Table dropped
SQL>
uj5u.com熱心網友回復:
如果我想將更新內容的時間和具體哪個更新操作(update insert delect)都寫在B表上,能實作嗎uj5u.com熱心網友回復:
請舉例,最好用excel 畫一下。你想實作 什么。uj5u.com熱心網友回復:
uj5u.com熱心網友回復:
uj5u.com熱心網友回復:
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