Sql语句，怎样让pFileName只出现一次解决办法_Sql Server

Sql语句，怎样让pFileName只出现一次
表加入如下所示

mId pId pFileName
20 | 4 | 123.jpg
22 | 3 | 123.jpg
7 | 6 | Chrysanthemum.jpg
27 | 4 | clouds.jpg
30 | 7 | flash.jpg
8 | 6 | Jellyfish.jpg
5 | 4 | mamechiyoShare.jpg
17 | 7 | mamechiyoShare.jpg
9 | 6 | Penguins.jpg
32 | 3 | Penguinsaaa.jpg
28 | 4 | pic_campus.jpg
21 | 3 | pic_campus.jpg
24 | 3 | pic_news04.jpg
4 | 4 | vs2010安装问题.png
29 | 3 | 沙漠.png
31 | 4 | 图片2.jpg
23 | 3 | 图片2.jpg

------解决方案--------------------

SQL code

select * from tb t where mid=(select min(mid) from tb where pFileName=t.pFileName)
------解决方案--------------------
SQL codeIF EXISTS (SELECT 1 FROM SYSOBJECTS WHERE name = 'tba')BEGIN    DROP TABLE tbaENDGOCREATE TABLE tba(    mId INT,    pId INT,    pFileName VARCHAR(100) )  INSERT INTO tbaSELECT 20,4,'123.jpg' UNIONSELECT 22,3,'123.jpg' UNIONSELECT 7,6,'Chrysanthemum.jpg' UNIONSELECT 27,4,'clouds.jpg' UNIONSELECT 30,7,'flash.jpg' UNIONSELECT 8,6,'Jellyfish.jpg' UNIONSELECT 5,4,'mamechiyoShare.jpg' UNIONSELECT 17,7,'mamechiyoShare.jpg' UNIONSELECT 9,6,'Penguins.jpg' UNIONSELECT 32,3,'Penguinsaaa.jpg' UNIONSELECT 28,4,'pic_campus.jpg' UNIONSELECT 21,3,'pic_campus.jpg' UNIONSELECT 24,3,'pic_news04.jpg' UNIONSELECT 4,4,'vs2010安装问题.png' UNIONSELECT 29,3,'沙漠.png' UNIONSELECT 31,4,'图片2.jpg' UNIONSELECT 23,3,'图片2.jpg' select mId,       pId,       pFileNamefrom tba tWHERE mId IN (SELECT TOP 1 mId FROM tba WHERE pFileName = t.pFileName)mId    pId    pFileName4    4    vs2010安装问题.png5    4    mamechiyoShare.jpg7    6    Chrysanthemum.jpg8    6    Jellyfish.jpg9    6    Penguins.jpg20    4    123.jpg21    3    pic_campus.jpg23    3    图片2.jpg24    3    pic_news04.jpg27    4    clouds.jpg29    3    沙漠.png30    7    flash.jpg32    3    Penguinsaaa.jpg