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id upperid
1 2
3 2
4 1
5 3
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Create table t(id int,upperid int)
insert into t
select 1, 2
union all select 3, 2
union all select 4, 1
union all select 5, 3
select * from t
create function aa(@upperid int)
returns @t table (id int,upperid int,level int)
as
begin
declare @i int
set @i=1
insert into @t
select *,@i from t where upperid=@upperid
while @@rowcount>0
begin
set @i=@i+1
insert into @t
select a.*,@i from t a left join @t b on a.upperid=b.id
where b.level=@i-1
end
return
end
select * from dbo.aa(1)
id upperid level
----------- ----------- -----------
4 1 1
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select * from dbo.aa(2)
id upperid level
----------- ----------- -----------
1 2 1
3 2 1
4 1 &nbs
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