--測試資料
if object_id('[t]') is not null drop table [t]
create table [t] (id int,pid int,name varchar(10))
insert into [t]
select 1,0,'a' union all
select 2,1,'b' union all
select 3,2,'c' union all
select 4,0,'d' union all
select 5,4,'e' union all
select 6,2,'f' union all
select 7,3,'g' union all
select 8,7,'h'
go--獲取所有的要根結點
select t.* from t t where exists (select 1 from t s where s.pid = t.id)
go--獲取所有的葉子結點
select t.* from t t where not exists (select 1 from t s where s.pid = t.id)
go--獲取樹型記錄的全路徑
if object_id('[dbo].[getallpath]') is not null
drop function [dbo].[getallpath]
gocreate function getallpath()
returns @t table(id int,pid int,name varchar(50),path varchar(300))
asbegin
insert into @t select id,pid,name,null as path from t
update @t set path=name
declare @i int,@j int
set @i=0
set @j=1
select @i=max(pid) from @t
while @j<=@i
begin
update v set path=a.path+'.'+v.name
from @t v inner join @t a on v.pid=a.id
where v.pid=@j
set @j=@j+1
endreturn
endgo
select * from getallpath()
go--獲取樹型記錄的全路徑
if object_id('[dbo].[getpath]') is not null
drop function [dbo].[getpath]
gocreate function getpath(@id varchar(20))
returns varchar(300)
asbegin
declare @s varchar(300)
select @s = name,@id = pid from t where id = @id
while exists (select 1 from t where id = @id )
select @s = name+'.'+@s,@id = pid from t where id = @id
return @s
endgo
select t.*,dbo.getpath(cast(id as varchar(20))) path from t
go--查詢樹
if object_id('[dbo].[getchild]') is not null
drop function [dbo].[getchild]
gocreate function getchild(@id int)
returns @returnt table(pid int,id int,name varchar(50))
as begin
insert into @returnt select pid,id,name from t where id=@id
insert into @returnt select pid,id,name from t where pid=@id
while @@rowcount>0
insert into @returnt select a.pid,a.id,a.name
from t a inner join @returnt b on a.pid=b.id
where a.id not in(select id from @returnt)
return
end
goselect * from getchild(1)
go--查詢樹型記錄的全路徑
if object_id('[dbo].[getfindpath]') is not null
drop function [dbo].[getfindpath]
gocreate function getfindpath(@parentid varchar(20))
returns @returndepartment table(id int,pid int,name varchar(50),path varchar(300))
asbegin
declare @t table(id int,pid int,name varchar(50),path varchar(300))
insert into @t select id,pid,name,null as path from t
update @t set path=name
declare @i int,@j int
set @i=0
set @j=1
select @i=max(pid) from @t
while @j<=@i
begin
update v set path=a.path+'.'+v.name
from @t v inner join @t a on v.pid=a.id
where v.pid=@j
set @j=@j+1
endinsert into @returndepartment select * from @t where id=@parentid
insert into @returndepartment select * from @t where pid=@parentid
while @@rowcount>0
insert into @returndepartment select a.id,a.pid,a.name,a.path
from @t a inner join @returndepartment b on a.pid=b.id
where a.id not in(select id from @returndepartment)
return
endgo
select * from getfindpath(1)
go
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