Oracle Tiger觸發(fā)器實(shí)例

--實(shí)例2------------------------
--創(chuàng)建觸發(fā)器，它將映射emp表中每個(gè)部門的總?cè)藬?shù)和總工資
--創(chuàng)建映射表
CREATE TABLE dept_sal
 AS
 SELECT deptno,COUNT(empno) AS total_emp,SUM(sal) AS total_sal FROM emp GROUP BY deptno;
DESC dept_sal;
--創(chuàng)建觸發(fā)器
CREATE OR REPLACE TRIGGER emp_info
AFTER INSERT OR UPDATE OR DELETE ON emp
DECLARE
 CURSOR cur_emp IS
   SELECT deptno,COUNT(empno) AS total_emp,SUM(sal) AS total_sal FROM emp GROUP BY deptno;
BEGIN
 DELETE dept_sal;  --觸發(fā)時(shí)首先刪除映射表信息
 FOR v_emp IN cur_emp LOOP
  --DBMS_OUTPUT.PUT_LINE(v_emp.deptno || v_emp.total_emp || v_emp.total_sal);
  --插入數(shù)據(jù)
  INSERT INTO dept_sal
   VALUES(v_emp.deptno,v_emp.total_emp,v_emp.total_sal);
 END LOOP;
END;
/
--對(duì)emp表進(jìn)行DML操作
INSERT INTO emp(empno,deptno,sal) VALUES('123','10',10000);
SELECT * FROM dept_sal;
DELETE EMP WHERE empno=123;
SELECT * FROM dept_sal;

--實(shí)例3------------------------
--創(chuàng)建觸發(fā)器，它記錄表的刪除數(shù)據(jù)
--創(chuàng)建表
CREATE TABLE employee
(
 id   VARCHAR2(4)  NOT NULL,
 name VARCHAR2(15) NOT NULL,
 age  NUMBER(2)    NOT NULL,
 sex  CHAR         NOT NULL
);
DESC employee;
--插入數(shù)據(jù)
INSERT INTO employee VALUES('e101','zhao',23,'M');
INSERT INTO employee VALUES('e102','jian',21,'F');
--創(chuàng)建記錄表
CREATE TABLE old_employee AS
 SELECT * FROM employee;
DESC old_employee;
--創(chuàng)建觸發(fā)器
CREATE OR REPLACE TRIGGER tig_old_emp
AFTER DELETE ON employee  --
FOR EACH ROW  --語(yǔ)句級(jí)觸發(fā)，即每一行觸發(fā)一次
BEGIN
 INSERT INTO old_employee
  VALUES(:old.id,:old.name,:old.age,:old.sex);  --:old代表舊值
END;
/
--下面進(jìn)行測(cè)試
DELETE employee;
SELECT * FROM old_employee;

--實(shí)例4------------------------
--創(chuàng)建觸發(fā)器，利用視圖插入數(shù)據(jù)
--創(chuàng)建表
CREATE TABLE tab1 (tid NUMBER(4) PRIMARY KEY,tname VARCHAR2(20),tage NUMBER(2));
CREATE TABLE tab2 (tid NUMBER(4),ttel VARCHAR2(15),tadr VARCHAR2(30));
--插入數(shù)據(jù)
INSERT INTO tab1 VALUES(101,'zhao',22);
INSERT INTO tab1 VALUES(102,'yang',20);
INSERT INTO tab2 VALUES(101,'13761512841','AnHuiSuZhou');
INSERT INTO tab2 VALUES(102,'13563258514','AnHuiSuZhou');
--創(chuàng)建視圖連接兩張表
CREATE VIEW tab_view AS
 SELECT tab1.tid,tname,ttel,tadr FROM tab1,tab2
  WHERE tab1.tid = tab2.tid;
--創(chuàng)建觸發(fā)器
CREATE OR REPLACE TRIGGER tab_trigger
INSTEAD OF INSERT ON tab_view
BEGIN
 INSERT INTO tab1(tid,tname) VALUES(:new.tid,:new.tname);
 INSERT INTO tab2(ttel,tadr) VALUES(:new.ttel,:new.tadr);
END;
/
--現(xiàn)在就可以利用視圖插入數(shù)據(jù)
INSERT INTO tab_view VALUES(105,'zhaoyang','13886681288','beijing');
--查看效果
SELECT * FROM tab_view;

--實(shí)例5------------------------
--創(chuàng)建觸發(fā)器，比較emp表中更新的工資
CREATE OR REPLACE TRIGGER sal_emp
BEFORE UPDATE ON emp
FOR EACH ROW
BEGIN
 
 IF :OLD.sal > :NEW.sal THEN
  DBMS_OUTPUT.PUT_LINE('工資減少');
 ELSIF :OLD.sal < :NEW.sal THEN
  DBMS_OUTPUT.PUT_LINE('工資增加');
 ELSE
  DBMS_OUTPUT.PUT_LINE('工資未作任何變動(dòng)');
 END IF;
 DBMS_OUTPUT.PUT_LINE('更新前工資 ：' || :OLD.sal);
 DBMS_OUTPUT.PUT_LINE('更新后工資 ：' || :NEW.sal);
END;
/
--執(zhí)行UPDATE查看效果
UPDATE emp SET sal = 3000 WHERE empno = '7788';

--實(shí)例6------------------------
--創(chuàng)建觸發(fā)器，將操作CREATE、DROP存儲(chǔ)在log_info表
--創(chuàng)建表
CREATE TABLE log_info
(
 manager_user VARCHAR2(15),
 manager_date VARCHAR2(15),
 manager_type VARCHAR2(15),
 obj_name     VARCHAR2(15),
 obj_type     VARCHAR2(15)
);
--創(chuàng)建觸發(fā)器
CREATE OR REPLACE TRIGGER trig_log_info
AFTER CREATE OR DROP ON SCHEMA
BEGIN
 INSERT INTO log_info
  VALUES(USER,SYSDATE,SYS.DICTIONARY_OBJ_NAME,SYS.DICTIONARY_OBJ_OWNER,
   SYS.DICTIONARY_OBJ_TYPE);
END;
/
--測(cè)試語(yǔ)句
CREATE TABLE a(id NUMBER);
CREATE TYPE aa AS OBJECT(id NUMBER);
/
DROP TABLE a;
DROP TYPE aa;
--查看效果
SELECT * FROM log_info;

--相關(guān)數(shù)據(jù)字典-----------------------------------------------------//
SELECT * FROM USER_TRIGGERS;
SELECT * FROM ALL_TRIGGERS;
SELECT * FROM DBA_TRIGGERS;  --必須以DBA身份登陸才能使用此數(shù)據(jù)字典

--啟用和禁用
ALTER TRIGGER trigger_name DISABLE;
ALTER TRIGGER trigger_name ENABLE;