Compare files with duplicates in one file.

gy3c · New User Joined: 31 Aug 2022 Posts: 5 Location: India

Hello All,

Could someone please help me with a logic for the below requirement. I have two input files

Input file 1:(no duplicates)

100 data1
101 data2
102 data3
103 data4

File 2:

100 1
100 2
100 3
100 4
101 1
101 2
102 1
102 2
103 1
103 2
103 3
104 4

Output file 1:

100 1 data1
100 2
100 3
100 4
101 1 data2
101 2
102 1 data3
102 2
103 1 data4
103 2
103 3
103 4

Can someone help me how to accomplish this using cobol or sort ?

sergeyken · Posted: Wed Aug 31, 2022 10:53 pm

This question is not related in any manner neither to “COBOL programming”, nor to any other programming language.

This requires only your ability to think logically, and to design algorithms for various tasks.

In your case: you only need to join records from both inputs when 3-bytes keys are equal in both of them, AND the sequence number from the second input equals to 1.
In all other cases you need to use only the record from input two.

P.S.
Usually, this is covered at the Lesson #1 of any programming classes…

P.P.S.
It would be nice if you learned how to use the Code button, when posting your questions.

Joerg.Findeisen · Posted: Wed Aug 31, 2022 11:00 pm

It's 10 lines of SORT (or less) to achieve this. Also, z/OS mostly knows only Datasets.

gy3c · New User Joined: 31 Aug 2022 Posts: 5 Location: India

Thanks all for the response. The sequence number will not be always 1,2,3,4.It could be a random 3 digit code.sortee in ascending order.
I just posted an example..i will also try some coding today and let know for any doubts.

Joerg.Findeisen · Posted: Thu Sep 01, 2022 10:08 am

The beginning of the sequence number doesn't matter. It will always be the first entry from F2 that gets the additional data added. Sample:

gy3c · New User Joined: 31 Aug 2022 Posts: 5 Location: India

Yes,the beginning of sequence number doesn't matter.its always the first one. Because , the input file 2 will be anyways sorted

gy3c · New User Joined: 31 Aug 2022 Posts: 5 Location: India

can someone please let me know if the below logic would work ? and if there is any other easier way of doing it ?

read file1
read file 2

perform until EOF-FILE 1 OR EOF -FILE 2

If file1-key = file2-key
if FLAG-NOT SET
move data to output file
set flag-set to true
end-if
move file 2 to output layout

read file 1
read file 2
end-if

if file 1 < file 2
Write Output file from file 2
read file 1
end if

if file 1 > FILE 2
Write Output file from file 2
READ FILE 2
END-IF

END-PERFORM

Joerg.Findeisen · Posted: Thu Sep 01, 2022 2:16 pm

Sample, free of charge:

sergeyken · Posted: Thu Sep 01, 2022 6:48 pm

Again:

It would be nice if you learned how to use the Code button, when posting your questions.

Lynne · Active User Joined: 15 Jan 2015 Posts: 107 Location: USA

Read up on the JOIN for Sort (ICEMAN or Syncsort)
and then go thru Joerg.Findeisen's excellent simple example.

gy3c · New User Joined: 31 Aug 2022 Posts: 5 Location: India

hyeamit · New User Joined: 16 Apr 2009 Posts: 1 Location: Jaipur

Thank you. This is useful.