在 IN 中执行定义的变量时出现主元错误

Question

谁能告诉我为什么我这样做时会收到 "invalid number of arguments" 消息：

define mb1= ADD_MONTHS(TRUNC(SYSDATE,'MM')-1);

select *
from
(select COLLECTOR
,Month
,low_activity_days
from dwh_prod.low_activity_days_collect_t) src
pivot
(
sum(low_activity_days)
for month in (&mb1)
) piv;

谢谢！

Answer 1

缺少逗号

define mb1= ADD_MONTHS(TRUNC(SYSDATE,'MM'), -1);