从一个表中取出三列,
三类如下:
UserId pageUrl RefUrl1 p1 r11 p2 r32 p2 p33 p1 r13 p3 r3想得到如下结果
1 p1 r1
3 p1 r13 p3 r3
就是我要去掉第一列的重复,别的列我不管,怎么弄,谢了先
三类如下:
UserId pageUrl RefUrl1 p1 r11 p2 r32 p2 p33 p1 r13 p3 r3想得到如下结果
1 p1 r1
3 p1 r13 p3 r3
就是我要去掉第一列的重复,别的列我不管,怎么弄,谢了先
UserId pageUrl RefUrl1 p1 r1
2 p2 p33 p1 r1
UserId,
Min(pageUrl) As pageUrl,
Min(RefUrl) As RefUrl
From
TableName
Group By
UserId
UserId,
Max(pageUrl) As pageUrl,
Max(RefUrl) As RefUrl
From
TableName
Group By
UserId
where not exists (
select 1 from tablename
where UserId=a.UserId
and (pageUrl<a.pageUrl
or pageUrl=a.pageUrl
and RefUrl<RefUrl
)