sqlite 的case when 怎么写

select userid,  sum(CASE  ActualPay WHEN cast(ActualPay as int)<0 THEN 0 ELSE ShouldPay  END)-sum(CASE  ActualPay WHEN cast(ActualPay as int)<0 THEN 0 ELSE ActualPay  END) as overdraft  from xx group by userid

貌似不起作用
[解决办法]
sum(CASE WHEN 0+ActualPay<0 THEN 0 ELSE ShouldPay end)
[解决办法]
sql server的写法，你上面按个多了点东西：

SELECT  userid ,
         SUM(CASE WHEN CAST(ActualPay AS INT) < 0 THEN 0
                  ELSE ShouldPay
             END) - SUM(CASE WHEN CAST(ActualPay AS INT) < 0 THEN 0
                             ELSE ActualPay
                        END) AS overdraft
 FROM    xx
 GROUP BY userid