sql²éѯÓï¾ä

ÁÐ1        ÁÐ2    ÁÐ3
  Q1        1      1
  Q2_1      2      2
  Q2_2      2      2
  Q2_3      2      2
  Q31_1    4      4
  Q444_3    5      5
  Q444_5    5      5

ÎÒÏë²éѯ½á¹ûÊÇ£º
  Q1        1      1
  Q2_1      2      2
  Q31_1    4      4
  Q444_3    5      5

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SQL code:
SELECT MIN(ÁÐ1) ,ÁÐ2,ÁÐ3 from TB GROUP BY ÁÐ2,ÁÐ3

---

SQL code:
---²âÊÔÊý¾Ý---
if object_id('[tb]') is not null drop table [tb]
go
create table [tb]([col1] varchar(6),[col2] int,[col3] int)
insert [tb]
select 'Q1',1,1 union all
select 'Q2_1',2,2 union all
select 'Q2_2',2,2 union all
select 'Q2_3',2,2 union all
select 'Q31_1',4,4 union all
select 'Q444_3',5,5 union all
select 'Q444_5',5,5

---²éѯ---
select *
from tb t
where not exists(
selec