I'm using ESPER with JAVA and I'm trying to make a statement that performs a group-by DAY. the property is of DateTime type. I've tryed using
EPStatement cepStatement = cepAdm.createEPL("select sum((NVL(LST.value,TSUR.value)-10.0)/96.0) as add, LST.data.getDayOfMonth() as dia"+
" from LST.win:time(60 min), TSUR.win:time(60 min) "+
"where LST.data.getDayOfMonth() = TSUR.data.getDayOfMonth() and LST.data.getHourOfDay() = TSUR.data.getHourOfDay() "+
"and NVL(LST.value, TSUR.value)>10.0 "+
"Group by LST.data.getDayOfMonth()");
But I'm getting the error "Group-by expressions must refer to property names"...