触发器(适合初学者)_hive触发器

1、创建学生表与学生历史表

学生表:
-- Create table
create table STUDENT
(
  id   NUMBER(11) not null,
  name VARCHAR2(32),
  age  NUMBER(3)
)
tablespace USERS
  pctfree 10
  initrans 1
  maxtrans 255;
历史表:
CREATE TABLE STUDENT_H
AS SELECT * FROM STUDENT; /*复制学生表*/
alter table STUDENT_H add (student_id number(11) not null); /*添加字段 student_id*/
alter table STUDENT_H add (I_D_U VARCHAR2(32) not null);  /*添加字段 I_D_U 意为INSERT OR DELETE OR UPDATE*/
创建学生表序列:
-- Create sequence 
create sequence STUDENT_SEQ
minvalue 1
maxvalue 9999999999999999999999999999
start with 1
increment by 1
cache 20;
创建历史表序列:
-- Create sequence 
create sequence STUDENT_H_SEQ
minvalue 1
maxvalue 9999999999999999999999999999
start with 1
increment by 1
cache 20;
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33

创建触发器

在trigger上右键,找到NEW