Nav*_*eed 2 php sql group-by sql-order-by
我有这样一张桌子:
id| name | attendence
1 | Naveed| 1
2 | Naveed| 1
3 | Adil | 1
4 | Adil | 1
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我使用以下查询:
SELECT * FROM `test` WHERE `attendence`=1 GROUP BY name
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以上查询的结果:
id| name | attendence
3 | Adil | 1
1 | Naveed | 1
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上面的结果组按名称排,但显示每组的第一行.我想从每个组中选择最后一行(按id).
例如:
id| name | attendence
2 | Naveed | 1
4 | Adil | 1
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如何为上述结果编写查询.
谢谢
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
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可能甚至不再需要这个小组了.