mysql - MySQL中将n条记录合并为一条记录

Question

这个问题已经有答案了:

How to merge multiple rows in MySQL? (2 个回答)

已关闭 8 年前。

我有n条记录如下:

###Date Rank1 Rank2 Rank3 Rank4 Rank5 Rank6 Rank7  
10-01-2015    1    0    0    0    0    0    0   
10-01-2015    0    1    0    0    0    0    0   
10-01-2015    0    0    1    0    0    0    0   
10-01-2015    0    0    0    1    0    0    0   
10-01-2015    0    0    0    0    1    0    0   
10-01-2015    0    0    0    0    0    1    0   
10-01-2015    0    0    0    0    0    0    1  

我想要的输出是

### Date Rank1 Rank2 Rank3 Rank4 Rank5 Rank6 Rank7  
  10-01-2015    1    1    1    1    1    1    1  

有什么办法可以实现这一点吗？

Answer 1

您需要sum()和group by

select
Date,
sum(Rank1) as Rank1,
sum(Rank2) as Rank2,
sum(Rank3) as Rank3,
sum(Rank4) as Rank4,
sum(Rank5) as Rank5,
sum(Rank6) as Rank6,
sum(Rank7) as Rank7
from table_name
group by Date