这种查询要求的SQL语句应该怎么写

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Release: 2016-06-23 13:35:26
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表如下

A               B            
中国          1
中国          2
中国          3
美国          4
美国          5
英国          6
英国          7
.
.
.

-------------------最终查询出来结果要求是下面这样的
中国             1,2,3
美国             4,5
英国             6,7

我之前过直接用GROUP BY ,但A字段是能分组出来,但B字段的集合怎么出现呀?难道要再嵌一个SQL???


回复讨论(解决方案)

select A, group_concat(B) as B from 表 group by A
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select A, group_concat(B) as B from 表 group by A
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果然好用,但有点新问题,字段里同一组有相同值的B,如
A               B            
中国          1
中国          2
中国          1
中国          2
中国          1
-------------------------能显示成吗?我先研究一下上面的group_concat,说不定自己就能解决了,哈哈------------------------
中国          1,2

用了[DISTINCT],好用,谢谢楼上,结分

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