with ts as ( --首先要查询出最原始父级的信息 union all --全连接 select a.fitemclassid,a.fitemid, a.fnumber,a.Fparentid,a.fname,a.FFullNumber from t_item a inner join ts b on a.Fparentid=b.fitemid --将整体的查询结果重新嵌套进语句中,将查询结果集中子类的ID与父类ID关联,进行查询 ) select * from ts order by…