Oracle主鍵自增

1、創建table

CREATE TABLE demo6
(
    id INT NOT NULL,
    key1 VARCHAR2(40) NULL,
    key2 VARCHAR2(40) NULL
);

2、設置主鍵

alter table demo6 add constraint demo6_pk primary key (id);

3、新建序列

create sequence demo6_id
minvalue 1
nomaxvalue 
increment by 1 
start with 1
nocache;

4、新建觸發器

create or replace trigger demo6_tg_insertId
before insert on demo6 for each row 
begin
  select demo6_id.Nextval into:new.id from dual;
end;

5、插入數據

insert into demo6 (key1, key2)
values ('key1', 'key2');
insert into demo6 (key1, key2)
values ('key11', 'key22');

6、查詢table

select * from demo6;

 7、查詢當前序列值

select demo6_id.currval from dual;

參考文章：http://www.cnblogs.com/dshore123/p/8267240.html

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