例
000001 IDENTIFICATION DIVISION.
000002 PROGRAM-ID. C1327.
000003 ENVIRONMENT DIVISION.
000004 INPUT-OUTPUT SECTION.
000005 FILE-CONTROL.
000006 SELECT IN-F ASSIGN I-SYS000
000007 RECORD KEY IS FNO WITH DUPLICATES
000008 ORGANIZATION IS SEQUENTIAL
000009 WITH DUPLICATES
000010 .
000011 DATA DIVISION.
000012 FILE SECTION.
000013 FD IN-F.
000014 01 IN-R.
000015 02 FNO PIC 9(4).
000016 02 FNAME PIC X(30).
000017 END PROGRAM C1327.
C1327.cob (9) : JMN1327I-S RECORD KEY句のDUPLICATES指定は，索引ファイル以外に記述できません．