Oracle触发器的创建使用及查询

--ORACLE查出表所有的触发器及触发器详细信息
--1.查all_triggers表得到trigger_name Sql代码
select trigger_name from all_triggers where table_name='tUsers';
 
--2.根据trigger_name查询出触发器详细信息 Sql代码   
select text from all_source where type='TRIGGER' AND name='TR_USER';
 
 
 
--测试建表语句
CREATE TABLE tUsers(
     UserID INT PRIMARY KEY,
     UserName VARCHAR(30),
     UserPassword VARCHAR(32),
     LastTime DATE
 ); 
 
 --建立一个sequence序列 
 CREATE SEQUENCE USER_ID_SEQ INCREMENT BY 1 START WITH 1;
 
 --建立一个触发器: 
 CREATE OR REPLACE TRIGGER TR_USER
   BEFORE INSERT ON tUsers  
   FOR EACH ROW
 BEGIN
   SELECT USER_ID_SEQ.NEXTVAL INTO :NEW.UserID FROM DUAL;
 END TR_FCBOOK;
 
 --测试插入数据
 INSERT INTO tUsers(UserName,UserPassword) VALUES('admin','123456');
 INSERT INTO tUsers(UserName,UserPassword) VALUES('wh445306','123456');
 
 select * from tUsers
 
 truncate table tUsers
         
 --DROP TABLE tusers;
 --DROP SEQUENCE USER_ID_SEQ;
 --DROP TRIGGER TR_USER;