- SQL code
declare @test table( id int identity primary key, name nvarchar(20), Logo nvarchar(20))insert into @test values('aaa','aaa.jpg')insert into @test values('aaa',null)insert into @test values('bbb',null)insert into @test values('ccc',null)insert into @test values('ccc',null)insert into @test values('ccc','ccc.jpg')insert into @test values('bbb','bbb.jpg')insert into @test values('ddd','ddd.jpg')
需要结果:
id name logo
1 aaa aaa.jpg
4 ccc null
5 bbb bbb.jpg
6 ddd ddd.jpg
解释下:就是说按照name分组排序,条件是如果有N条,那么取logo不为空的那条,如果只有一条,那么无论为空不为空都显示出来。
谢谢大家。
蛋疼,刚才null加引号了。郁闷
------解决方案--------------------
- SQL code
declare @test table( id int identity primary key, name nvarchar(20), Logo nvarchar(20))insert into @test values('aaa','aaa.jpg')insert into @test values('aaa',null)insert into @test values('bbb',null)insert into @test values('ccc',null)insert into @test values('ccc',null)insert into @test values('ccc','ccc.jpg')insert into @test values('bbb','bbb.jpg')insert into @test values('ddd','ddd.jpg')select distinct t.* from @test across apply(select top 1 * from @test where name=a.name order by Logo desc) t/*id name Logo----------- -------------------- --------------------1 aaa aaa.jpg6 ccc ccc.jpg7 bbb bbb.jpg8 ddd ddd.jpg(4 行受影响)
------解决方案--------------------
- SQL code
declare @test table( id int identity primary key, name nvarchar(20), Logo nvarchar(20))insert into @test values('aaa','aaa.jpg')insert into @test values('aaa',null)insert into @test values('bbb',null)insert into @test values('ccc',null)insert into @test values('ccc',null)insert into @test values('ccc','ccc.jpg')insert into @test values('bbb','bbb.jpg')insert into @test values('ddd','ddd.jpg')insert into @test values('eee',null)select * from @test a where isnull(Logo,'')=(select isnull(max(Logo),'') from @test where name=a.name)/*id name Logo----------- -------------------- --------------------1 aaa aaa.jpg6 ccc ccc.jpg7 bbb bbb.jpg8 ddd ddd.jpg9 eee NULL*/