如何实现count(TickState=2)这种样式?
select count(TickState) as UseTotal,count(TickState=2) as WasteTotal
from toll_list
就是一个字段有3种取值,取出每种取值的记录数.
但是不能用该字段group.因为还要取其它值.
谢谢!
[解决办法]
select count(TickState) as UseTotal,sum(case when TickState=2 then 1 else 0 end) as WasteTotal
from toll_list
[解决办法]
select UseTotal = sum(case TickState when 1 then 1 else 0 end),
WasteTotal = sum(case TickState when 2 then 1 else 0 end)
from toll_list
