create function iterate_fun(@id int)
returns @t table(id int,parentid int,level int)
begin
declare @i int
set @i=1
insert @t select id,parent_id,@i from b_project_land where
parent_id=@id
while @@rowcount<>0
begin
set @i=@i+1
insert @t select pl.id,pl.parent_id,@i from b_project_land pl,@t b
where b.id=pl.parent_id and
b.level=@i-1
end
return
end
