×îºó20·Ö,Çó1ÌõSQL - MS-SQL Server / »ù´¡Àà

id name
1 СÕÅ
2 СÀî
3 С³Â


id1 id2 id3
1 3 2
3 2 2

ÒªÇó½á¹û-----------------
id1 id2 id3
СÕŠС³Â СÀî
С³Â СÀî СÀî

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SQL code:
left join

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SQL code:
select (select name from tb where id=id1) as id1
from tb2

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SQL code:
select a.name,b.name,c.name from tb t
left join ta a on t.id1=a.id
left join ta b on t.id2=b.id
left join ta b on t.id3=c.id

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ÒýÓÃ

SQL code
select a.name,b.name,c.name from tb t
left join ta a on t.id1=a.id
left join ta b on t.id2=b.id
left join ta b on t.id3=c.id

ok?
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SQL code:
--> ²âÊÔÊý¾Ý: #T1
if object_id('tempdb.dbo.#T1') is not null drop table #T1
create table #T1 (id int,name varchar(4))
insert into #T1
select 1,'СÕÅ' union all
select 2,'СÀî' union all
select 3,'С³Â'
--> ²âÊÔÊý¾Ý: #T2
if object_id('tempdb.dbo.#T2') is not null drop table #T2
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