oracle建立序列

create table sms_activity(

id number,

activity_name varchar2(50),

begin_time varchar2(30),

end_time varchar2(30),

content varchar2(600)
)

表已创建。

SQL> commit;

提交完成。

SQL> alter table sms_activity addprimary key (id);

表已更改。

SQL> commit;

提交完成。

SQL> create sequence sms_activity_seq

2  minvalue 1

3  maxvalue 9999999999

4  increment by 1

5  cache 20

6  ;

序列已创建。

SQL> create or replace triggerbi_activity

2  before insert on sms_activity

3  for each row

4  begin

5  select sms_activity_seq.nextval into  :NEW.ID  from dual;

6  end;

7  /

触发器已创建

SQL>desc  sms_activity

名称                                      是否为空? 类型

------------------------------------------------- ----------------------------

ID                                        NOTNULL NUMBER

ACTIVITY_NAME                                     VARCHAR2(50)

BEGIN_TIME                                        VARCHAR2(30)

END_TIME                                          VARCHAR2(30)

CONTENT                                           VARCHAR2(600)

SQL> alter table sms_activity add(create_time varchar2(30),createby varchar2(20),modify_timevarchar2(30),modifyby varchar2(20));

表已更改。

SQL> commit;

创建序列
create sequence  seq_createid
minvalue 1  maxvalue 999999
increment by 1
start with 1
cache 20
noorder cycle;
创建触发器
create or replace trigger  tr_createid
before insert on tb_user
for each row
when(new.id is null)
begin
select seq_createid.nextval into  :new.id  from dual;
end;