The input file have records as: 8712351,8712353,8712353,8712354,8712356,8712352,8712355 8712352,8712355
Using COBOL, I need to remove duplicates from the above file and write to an output file. I wrote simple logic to read records and write to an output file.
Where do I need to put the logic of removing duplicates (say, 8712353, 8712352) from the above file?
Here is the program logic:
IDENTIFICATION DIVISION.
PROGRAM-ID.RemoveDup.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT INPUTFILEDUP ASSIGN TO 'C:\Cobol\INPUTFILEDUP.txt'
ORGANIZATION IS LINE SEQUENTIAL.
SELECT OUTFILEDUP ASSIGN TO 'C:\Cobol\OUTFILEDUP.txt'
ORGANIZATION IS LINE SEQUENTIAL.
DATA DIVISION.
FILE SECTION.
FD INPUTFILEDUP.
01 INPUTFILEDUPREC.
88 EOFINPUTFILEDUP VALUE HIGH-VALUES.
02 INPUTFILEID PIC 9(07).
FD OUTFILEDUP.
01 OUTFILEDUPREC PIC 9(07).
WORKING-STORAGE SECTION.
77 WS-VARIABLE PIC 9(09).
77 REC-NOT-MATCH PIC 9(01).
77 CUR-VARIABLE PIC 9(09).
PROCEDURE DIVISION.
BEGIN.
OPEN INPUT INPUTFILEDUP
OPEN OUTPUT OUTFILEDUP
READ INPUTFILEDUP
AT END SET EOFINPUTFILEDUP TO TRUE
END-READ
PERFORM UNTIL (EOFINPUTFILEDUP)
WRITE OUTFILEDUPREC FROM INPUTFILEID
READ INPUTFILEDUP
AT END SET EOFINPUTFILEDUP TO TRUE
PERFORM UNTIL (EOFINPUTFILEDUP)
END-READ
END-PERFORM
CLOSE INPUTFILEDUP
CLOSE OUTFILEDUP
STOP RUN.
I sorted the tnput file in ascending order as:
8712351,8712353,8712353,8712354,8712356,8712352,8712355,8712352,8712355
And it worked, and below is the modified code:
But suppose if my file is not in either ascending or descending order the where I need to write the sort logic before removing duplicates. How can update the below code for this? As I tried, but I was not successful in doing this if the input file structure is like:
8712351,8712353,8712353,8712354,8712356,8712352,8712355,8712352,8712355
IDENTIFICATION DIVISION.
PROGRAM-ID.RemoveDup2.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT INPUTFILEDUP ASSIGN TO 'C:\Cobol\INPUTFILEDUP.txt'
ORGANIZATION IS LINE SEQUENTIAL.
SELECT OUTFILEDUP ASSIGN TO 'C:\Cobol\OUTFILEDUP.txt'
ORGANIZATION IS LINE SEQUENTIAL.
DATA DIVISION.
FILE SECTION.
FD INPUTFILEDUP.
01 INPUTFILEDUPREC.
88 EOFINPUTFILEDUP VALUE HIGH-VALUES.
02 INPUTFILEID PIC 9(07).
FD OUTFILEDUP.
01 OUTFILEDUPREC PIC 9(07).
WORKING-STORAGE SECTION.
77 WS-VARIABLE PIC 9(09) VALUE ZERO.
77 REC-NOT-MATCH PIC 9(01).
77 CUR-VARIABLE PIC 9(7) VALUE ZERO.
PROCEDURE DIVISION.
BEGIN.
OPEN INPUT INPUTFILEDUP
OPEN OUTPUT OUTFILEDUP
READ INPUTFILEDUP
AT END SET EOFINPUTFILEDUP TO TRUE
END-READ
PERFORM UNTIL (EOFINPUTFILEDUP)
IF INPUTFILEID NOT EQUAL TO WS-VARIABLE
MOVE INPUTFILEID TO WS-VARIABLE
WRITE OUTFILEDUPREC FROM INPUTFILEID
READ INPUTFILEDUP
AT END SET EOFINPUTFILEDUP TO TRUE
PERFORM UNTIL (EOFINPUTFILEDUP)
ELSE
DISPLAY "dUPLICATE FOUND" INPUTFILEID
READ INPUTFILEDUP
AT END SET EOFINPUTFILEDUP TO TRUE
END-READ
END-PERFORM
CLOSE INPUTFILEDUP
CLOSE OUTFILEDUP
STOP RUN.
sort is standard for these OS close jobs to follow the DRY principle. Gears -t for separator and -u for uniques. It's C.