Sql 如何在一定条件下创建更新触发器?
我想创建一个触发器,该触发器强制执行以下条件:声明为“详细信息”列只能在放置后3天内更改 我有Sql 如何在一定条件下创建更新触发器?,sql,oracle,oracle11g,database-trigger,Sql,Oracle,Oracle11g,Database Trigger,我想创建一个触发器,该触发器强制执行以下条件:声明为“详细信息”列只能在放置后3天内更改 我有OrderId,详细信息,OrderDate列 我该怎么做?你能帮忙吗?这里有一个例子 首先,测试用例: SQL> alter session set nls_date_format = 'dd.mm.yyyy'; Session altered. SQL> create table test 2 (orderid number primary key, 3 d
OrderId
,详细信息
,OrderDate
列
我该怎么做?你能帮忙吗?这里有一个例子
首先,测试用例:
SQL> alter session set nls_date_format = 'dd.mm.yyyy';
Session altered.
SQL> create table test
2 (orderid number primary key,
3 details varchar2(20),
4 orderdate date
5 );
Table created.
SQL> insert into test (orderid, details, orderdate)
2 select 1, 'test 1', date '2018-10-15' from dual union all
3 select 2, 'test 2', date '2018-10-22' from dual;
2 rows created.
SQL> select sysdate from dual;
SYSDATE
----------
23.10.2018
SQL> select * from test;
ORDERID DETAILS ORDERDATE
---------- -------------------- ----------
1 test 1 15.10.2018
2 test 2 22.10.2018
SQL>
触发:
SQL> create or replace trigger trg_bu_test
2 before update of details on test
3 for each row
4 begin
5 if trunc(sysdate) - :new.orderdate > 3 then
6 raise_application_error(-20001, 'More than 3 days have passed; update is not allowed');
7 end if;
8 end;
9 /
Trigger created.
测试:
SQL> -- ID = 1 - 8 days have passed, no update is allowed
SQL> update test set details = 'xxx' where orderid = 1;
update test set details = 'xxx' where orderid = 1
*
ERROR at line 1:
ORA-20001: More than 3 days have passed; update is not allowed
ORA-06512: at "SCOTT.TRG_BU_TEST", line 3
ORA-04088: error during execution of trigger 'SCOTT.TRG_BU_TEST'
SQL> -- ID = 2 - 1 day passed - update is allowed
SQL> update test set details = 'yyy' where orderid = 2;
1 row updated.
SQL>
p.S.而不是
触发器(您在问题中提到)用于视图;忘掉它们(在这种情况下)。下面是一个例子
首先,测试用例:
SQL> alter session set nls_date_format = 'dd.mm.yyyy';
Session altered.
SQL> create table test
2 (orderid number primary key,
3 details varchar2(20),
4 orderdate date
5 );
Table created.
SQL> insert into test (orderid, details, orderdate)
2 select 1, 'test 1', date '2018-10-15' from dual union all
3 select 2, 'test 2', date '2018-10-22' from dual;
2 rows created.
SQL> select sysdate from dual;
SYSDATE
----------
23.10.2018
SQL> select * from test;
ORDERID DETAILS ORDERDATE
---------- -------------------- ----------
1 test 1 15.10.2018
2 test 2 22.10.2018
SQL>
触发:
SQL> create or replace trigger trg_bu_test
2 before update of details on test
3 for each row
4 begin
5 if trunc(sysdate) - :new.orderdate > 3 then
6 raise_application_error(-20001, 'More than 3 days have passed; update is not allowed');
7 end if;
8 end;
9 /
Trigger created.
测试:
SQL> -- ID = 1 - 8 days have passed, no update is allowed
SQL> update test set details = 'xxx' where orderid = 1;
update test set details = 'xxx' where orderid = 1
*
ERROR at line 1:
ORA-20001: More than 3 days have passed; update is not allowed
ORA-06512: at "SCOTT.TRG_BU_TEST", line 3
ORA-04088: error during execution of trigger 'SCOTT.TRG_BU_TEST'
SQL> -- ID = 2 - 1 day passed - update is allowed
SQL> update test set details = 'yyy' where orderid = 2;
1 row updated.
SQL>
p.S.
而不是
触发器(您在问题中提到)用于视图;忘记它们(在这种情况下)。尝试使用AFTER触发器
create or replace TRIGGER TR_details_update
AFTER UPDATE ON order_det
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
IF UPDATING THEN
IF NVL(:OLD.Details, 'XXX') <> NVL(:NEW.Details, 'XXX') AND :OLD.OrderDate <= TRUNC(SYSDATE) - 3 THEN
update order_det
set Details = :new.Details
where Details = :old.Details
and OrderId = :old.OrderId;
END IF;
END IF;
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR (-20000,'Details must be changed within 3 days of order date');
END TR_details_update;
创建或替换触发器TR\u详细信息\u更新
订单数据更新后
引用新旧相同
每行
开始
如果更新,则
如果NVL(:OLD.Details,'XXX')NVL(:NEW.Details,'XXX')和:OLD.OrderDate请尝试使用AFTER触发器
create or replace TRIGGER TR_details_update
AFTER UPDATE ON order_det
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
IF UPDATING THEN
IF NVL(:OLD.Details, 'XXX') <> NVL(:NEW.Details, 'XXX') AND :OLD.OrderDate <= TRUNC(SYSDATE) - 3 THEN
update order_det
set Details = :new.Details
where Details = :old.Details
and OrderId = :old.OrderId;
END IF;
END IF;
EXCEPTION
WHEN OTHERS THEN
RAISE_APPLICATION_ERROR (-20000,'Details must be changed within 3 days of order date');
END TR_details_update;
创建或替换触发器TR\u详细信息\u更新
订单数据更新后
引用新旧相同
每行
开始
如果更新,则
如果NVL(:OLD.Details,'XXX')NVL(:NEW.Details,'XXX')和:OLD.OrderDate,您是否可以尝试自己创建它?甚至为更新触发器挖掘任何文档,比如,都会给你更多的想法/尝试,让你自己写这篇文章,而不是你目前所拥有的。你能尝试一下自己创建它吗?即使是为更新触发器挖掘任何文档,比如,也会给你比目前更多的想法/尝试,让你自己写这篇文章。为什么在触发器之后是,而不是在触发器之前是?在更新后触发器中,您还会做什么?为什么要在触发器中更新
?在代码中,您什么也不做。另外,您希望出现哪种例外情况?这应该是其他的一部分,而不是例外。我得到了变异错误。。所以我改成在触发后。。。我在块内进行了更新,但在我看到您的触发器后,这是不必要的…谢谢为什么在
触发器之后是,而不是在
触发器之前是?在更新后触发器中,您还会做什么?为什么要在触发器中更新
?在代码中,您什么也不做。另外,您希望出现哪种例外情况?这应该是其他的一部分,而不是例外。我得到了变异错误。。所以我改成在触发后。。。我在块内进行了更新,但在我看到你的触发器后,这是不必要的…谢谢一切都很好,以可以理解的方式解释,一步一步,非常感谢一切都很好,以可以理解的方式解释,一步一步,非常感谢