【SQL练习题】一个连续性问题的题目

题目如下：

—1.建表

create table t_group(
id number,
name varchar2(20));

—2.插入数据

insert into t_group values(1,'/');
insert into t_group values(2,'A');
insert into t_group values(3,'B');
insert into t_group values(4,'C');
insert into t_group values(5,'/');
insert into t_group values(6,'D');
insert into t_group values(7,'E');
insert into t_group values(8,'/');
insert into t_group values(9,'F');
insert into t_group values(10,'G');
insert into t_group values(11,'H');
commit;

解题思路：

最终语句:

select id, name, id - row_number() over(order by id) as group_id
  from t_group
 where name != '/';