添加数据库表自增列

1.创建数据库表
-- Create table
create table T_MOBILE_BRAND
(
  ID   NUMBER not null,
  NAME VARCHAR2(200)
)
tablespace MASS_DATA
  pctfree 10
  initrans 1
  maxtrans 255
  storage
  (
    initial 2M
    next 2M
    minextents 1
    maxextents unlimited
    pctincrease 0
  );
-- Create/Recreate primary, unique and foreign key constraints
alter table T_MOBILE_BRAND
  add constraint T_MOBILE_BRAND_PK primary key (ID)
  using index
  tablespace MASS_DATA
  pctfree 10
  initrans 2
  maxtrans 255
  storage
  (
    initial 2M
    next 2M
    minextents 1
    maxextents unlimited
    pctincrease 0
  );
2.创建Sequence
-- Create sequence
create sequence SEQ_BRAND_ID
minvalue 1
maxvalue 9999999999999999999999999999
start with 741
increment by 1
cache 20;
3.创建触发器
CREATE OR REPLACE TRIGGER ADD_BRAND_ID BEFORE
INSERT ON T_MOBILE_BRAND FOR EACH ROW
BEGIN
  SELECT SEQ_BRAND_ID.NEXTVAL INTO :NEW.ID
  FROM DUAL;
END;