详细参照:https://www.2cto.com/database/201303/196830.html
create sequence seq_xxx; 创建 seq_xxx序列
alter sequence seq_xxx restart with 10; 修改seq_xxx序列值从10开始 (省略with 10就是从0开始计数)
select nextval for seq_xxx from sysibm.sysdummy1 ; 查看下一序列值
select prevval for seq_xxx from sysibm.sysdummy1 ; 查看当前序列值
alter sequence seq_xxx increment by 10 ; 修改序列值的自增值