作者joedenkidd (优质的蓝色射手)
看板Database
标题Re: [SQL ] table中分群做count
时间Thu May 4 20:54:33 2017
select date,count(case when value='a' then 1 else null end) as count_a,count(case when value='b' then 1 else null end) as count_b from table group by date
这样应该可以达到你要的结果
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1F：推 Czero: Thanks~! 05/04 21:23