ISNULL函数起作用的前提是 该条数据存在
可以先通过 IF EXISTS 来判断是否存在
IF EXISTS ( SELECT ISNULL( CASE WHEN (SELECT COUNT(1) FROM beau_User where UserId=mpo.superior_user_id and PID='10539300278' )>0 THEN (ISNULL(mpo.buy_commission, 0)+ISNULL(mpo.superior_commission, 0))/1000 ELSE
(ISNULL(mpo.buy_commission, 0)+ISNULL(mpo.head_commission, 0))/1000 END,0) p
from mm_pdd_order mpo where mpo.head_user_id='59686498966192128' and create_time >='2020-02-01' and (order_status !=-1 and order_status !=4 and order_status !=8 and order_status !=10) ) BEGIN SELECT ISNULL( CASE WHEN (SELECT COUNT(1) FROM beau_User where UserId=mpo.superior_user_id and PID='10539300278' )>0 THEN (ISNULL(mpo.buy_commission, 0)+ISNULL(mpo.superior_commission, 0))/1000 ELSE
(ISNULL(mpo.buy_commission, 0)+ISNULL(mpo.head_commission, 0))/1000 END,0) p
from mm_pdd_order mpo where mpo.head_user_id='59686498966192128' and create_time >='2020-02-01' and (order_status !=-1 and order_status !=4 and order_status !=8 and order_status !=10) END ELSE BEGIN --如果不存在 SELECT 0 p END
