.-,------------------------------.      
          |                  .-,---.       |      
          V                  V     |       |      
>>-BY--(----(--schar,op,--(----arg-+--)--)-+--)----------------><

BY specifies that the data sets selected up to this point, by the processing of the INCLUDE and EXCLUDE keywords, are to be filtered further. To select the data set, all BY criteria must be met. See Filtering by data set characteristics for a full discussion of schar, op, arg, and for more information about BY filtering.