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我正在使用 SQL 2005，现有数百万条记录的数据（因此无法更改数据结构）并且我正在尝试执行以下操作：

我在自引用表中有一些数据（以下示例来自另一个问题，并进行了一些修改以显示我想要实现的目标）。我需要按以下格式提取结果树：

Parent
 Child1 of Parent
  Child1 of Child 1
  Child2 of Child 1
 Child2 of Parent
  Child1 of Child 2

我的实际数据有 9 个深度 - 我尝试使用 CTE 获得结果。但是，这会产生以下结果：

Parent
 Child1 of Parent
 Child2 of Parent
  Child1 of Child 1
  Child2 of Child 1
  Child1 of Child 2

这是我正在使用的查询类型的示例：

create table workshop (
w_id smallint primary key,
p_id smallint,
s_date smalldatetime,
title varchar(100))
go

alter table workshop add constraint fk_wkshp foreign key (p_id)
references workshop(w_id)
go

insert into workshop (w_id, p_id, s_date, title) values (1, null,
'5/2/2007', 'Parent')
insert into workshop (w_id, p_id, s_date, title) values (2, 1,
'5/3/2007', 'Child 1 of the parent')
insert into workshop (w_id, p_id, s_date, title) values (3, 1,
'5/5/2007', 'Child 2 of the parent')
insert into workshop (w_id, p_id, s_date, title) values (4, 2,
'5/4/2007', 'Child of Child 1')
insert into workshop (w_id, p_id, s_date, title) values (5, 2,
'5/5/2007', 'Child 2 of the child of the parent')
insert into workshop (w_id, p_id, s_date, title) values (6, 3,
'5/7/2007', 'Child of the child 2')
insert into workshop (w_id, p_id, s_date, title) values (7, null,
'5/7/2007', '2nd Parent')
insert into workshop (w_id, p_id, s_date, title) values (8, 7,
'5/7/2007', 'Child of 2nd Parent')
insert into workshop (w_id, p_id, s_date, title) values (9, 7,
'5/7/2007', 'Child of 2nd Parent')
go

declare @id smallint
set @id = 1

;with events (w_id, p_id, s_date, title)
as
(
-- the anchor member
select
w_id, p_id, s_date, title
from
workshop
where w_id = @id

-- the recursive member
union all

select
w.w_id, w.p_id, w.s_date, w.title
from
workshop w
-- the key is to join to the CTE
join events e on e.w_id = w.p_id
)

select * from events

drop table workshop
go

我已经看到与此相关的各种其他问题，但看不到我的问题的答案。最接近的事情是 oracle 'connect by prior' 如果我使用的是 oracle dB，那就太好了！有任何想法吗？

干杯，杰森

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1 回答 1

0

我想我已经找到了答案，那就是我加入的是锚定成员，而不是研讨会的桌子。感谢 gjvdkamp 提供了这篇类似的帖子，它让我重新评估了错误的“真实”sql 语句。

于 2011-03-31T11:51:38.327 回答