text: 
  --create database graphh;
  
  create type graphh_value AS(id int,value float8,other int);
  create type vertex_ AS(flag int,to_node int,value graphh_value);
  create table vertex(flag int,value graphh_value) distributed by (flag);
  create table edge(from_node int,to_node int) distributed by (from_node);
  
  -- 后续版本考虑加入以顶点为中心算法模型中的active设计考虑，需要加入v_update表来模拟顶点活跃
  -- create table v_update(flag int,value graphh_value) distributed by (flag);   
  
  
  