oracle序列号的操作

oracle里面没得主键自增不像mysql，要自定义序列号

如何修改序列号

1..查询最新一条记录的序列号
select seq from (select * from CH_T_PRODUCT_MUSIC  order by seq desc) where rownum=1;

4831163         
select SEQ_PRODUCT_MUSIC.nextval from dual;

2.删除老的序列号
drop SEQUENCE SEQ_PRODUCT_MUSIC;


3.create sequence SEQ_PRODUCT_MUSIC
minvalue 1
maxvalue 999999999999999999999999999
start with 4831164          
increment by 1
cache 20;