LastTime__c false IF( ISBLANK(Start_time__c), (TIMEVALUE(IsScheduled_EndDateTime__c) - TIMEVALUE(IsScheduled_StartDateTime__c))/1000/60/60, (TIMEVALUE(EndDateTime__c) - TIMEVALUE(StartDateTime__c))/1000/60/60) BlankAsZero 持续时间 18 false 2 false false Number false