一 sql 的写法
table
year result
2013 fail
2013 succ
2013 succ
2012 succ
2012 fail
2011 succ
输出
year succ fail
2013 2 1
2012 1 1
2011 1 0
只会写到这里,
而且感觉这个写法不好,不知有没更好的写法
select year1,
sum(case result when 'succ' then 1 else 0 end) succ,
sum(case result when 'fail' then 1 else 0 end) fail
from #c
group by year1