douti9286 2010-08-10 14:01
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SQL:GROUP BY记录,然后从每个组获取最后一条记录? [重复]

Possible Duplicate:
SQL Server: Only last entry in GROUP BY

I have a table like this:

id| name  | attendence
1 | Naveed| 1
2 | Naveed| 1
3 | Adil  | 1
4 | Adil  | 1

I use following query:

SELECT * FROM `test` WHERE `attendence`=1 GROUP BY name

The result with above query:

id| name   | attendence
3 | Adil   | 1
1 | Naveed | 1

Question:

Above result group rows by name but show first row from each group. I want to select last row(by id) from each group.

For example:

id| name   | attendence
2 | Naveed | 1
4 | Adil   | 1

How to write query for above result.

Thanks

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4条回答 默认 最新

  • dsv17139 2010-08-10 14:04
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    SELECT a.* 
    FROM test a 
    WHERE a.attendence = 1 
    AND NOT EXISTS (select 1 from test where name = a.name and id > a.id and attendence = 1)
    GROUP BY name 
    

    Might not even need the group by anymore.

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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