select bm, count(*) as icount from tab group by bm;
你自己稍微可以变通一下呀select bm, lx, count(*) as icount from tab group by bm, lx;
行转列的问题,论坛里一大堆呀 select bm, sum(case when lx = 1 then count(*) else 0 end) as "类型1", sum(case when lx = 2 then count(*) else 0 end) as "类型2", ... ... sum(case when lx = N then count(*) else 0 end) as "类型N" from tab group by bm, lx;
select bm, count(*) as icount
from tab
group by bm;
你自己稍微可以变通一下呀select bm, lx, count(*) as icount
from tab
group by bm, lx;
select bm,
sum(case when lx = 1 then count(*) else 0 end) as "类型1",
sum(case when lx = 2 then count(*) else 0 end) as "类型2",
... ...
sum(case when lx = N then count(*) else 0 end) as "类型N"
from tab
group by bm, lx;
这个我刚才也找到了个 ,如果加了bm这个字段进行查询会报出 “不是单分组函数”这个错 ,而情况是我要通过bm这个字段分组
select bm,
sum(case when lx = 1 then 1 else 0 end) as "类型1",
sum(case when lx = 2 then 1 else 0 end) as "类型2"
from t
group by bm