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Sage ACCPAC ERP
» group by 与 order by
erina.pan
发表于 2016-9-5 17:40
group by 与 order by
group by
1.对重复的数据合并分组,
(group by a,b a列和b列的行数据相等才会合并)
2.分组筛选(having\聚合函数)
3.对各分组数据进行统计(聚合函数)
order by
order by a,b (先按a排序再按b排序)
页:
[1]
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