IF
report:Â IF([date1]=1; "Jan" ;
         IF ([date1]=2; "Feb" ;
         IF ([date1]=3; "Mar" ;
         IF ([date1]=4; "Apr" ;
         IF ([date1]=5; "May" ;
         IF ([date1]=6; "Jun" ;
         IF ([date1]=7; "Jul" ;
         IF ([date1]=8; "Aug" ;
         IF ([date1]=9; "Sep" ;
         IF ([date1]=10; "Oct" ;
         IF ([date1]=11; "Nov" ;
         "Dec" ; ) ) ) ) ) ) ) ) ) ) )