oracle之字段自增

在oracle中，当我们要让主键或者序号自增，然而oracle中没有像mysql那样有自增简单语句。但是我们可以通过序列与触发器来实现主键或者序列自增。

创建表

create table bank(

userId varchar2(10),

userName varchar2(10),

userPassword varchar2(20),

userMoney number(10,2),

constraint pk_userId PRIMARY KEY(userId)

);

序列

create sequence seq_bank

increment by 1

start with 1

nomaxvalue

nocycle

nocache;

触发器

create or replace trigger tri_bank

before insert on bank

for each row

begin

    select seq_bank.nextval into:new.userId from dual;

end;

commit;(别忘记提交事务)

添加数据后查询

insert into bank (userName,userpassword,usermoney) values ('张三','123456','1230.45');

insert into bank (userName,userpassword,usermoney) values ('张四','123456','1230.45');

select * from bank;