Specification File Qualifier
    Defines the input record fields to be used for a sort or merge
    operation or in a conditional evaluation, or whose order or
    format will change in the output record. You identify each field
    by specifying a name, its position and size in the record, and
    its data type.
    You can also use /FIELD to define a constant and assign it a
    value of any valid sort/merge data-type for use in /KEY, /DATA,
    and /CONDITION statements.
    Formats
      /FIELD=(NAME=field-name,POSITION:n,)
      SIZE:n,[DIGITS:n,]data-type
      /FIELD=(NAME=field-name,VALUE:n,)
      SIZE:n,[DIGITS:n,]data-type
Additional Information:
explode
extract