VMS Help PASCAL, Attributes, KEY  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The KEY attribute can be applied to record  fields  to  indicate
  that  the  field is to be used as a key field when the record is
  part of an indexed file.

  Syntax:

     KEY [[( n [[, {options},... ]] )]]
     KEY [[( {options},... )]]

  The 'n' represents the key number.  A key number of 0  indicates
  that  the field is the primary key of the record.  All other key
  numbers indicate alternate keys.   The  key  number  must  be  a
  constant  expression  that denotes an integer value in the range
  from 0 through 254.

  See the  "Compaq  Pascal  Language  Reference  Manual"  for  the
  complete description of using the KEY attribute.

  Additional Information (explode) :

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