cobol program to compare two seq. files

Rohit.sun123 · New User Joined: 01 Jun 2007 Posts: 1 Location: bangalore

There are 2 sequential files with records. Now we have to check for the matching records in both the files and put matched reords in a output file and unmatched records in a second output file.

srinivas_443 · New User Joined: 19 Dec 2007 Posts: 11 Location: chennai

Using cobol program we can do.

First open 2 file
Read file1(first rec)
Move record to WS-area1
Read file 2(first rec)
Move record to WS-area2

If WS-area1=WS-area2
Write to match-rec-file
Else
Write to diff-rec-file

This is my thought
Correct me if I am wrong

Regards,
Srinivas Jala

ashwinreddy · Posted: Tue Feb 12, 2008 3:42 pm

Hi Srinivas,

The above solution holds good for after sorting both the files with equal number of records in both the files.

Let me give you an example

file 1 file 2

1 3
2 1
3 4

If the files are in above format, then you may miss some records (almost all).

Slight modification in Srinivas logic

First open 2 file
Read file1(first rec)
Move record to WS-area1
Read file 2(first rec)
Move record to WS-area2

If WS-area1=WS-area2
Write to match-rec-file
Else

Perform the 2nd file read until match found with the first file

If match found
Write to match-rec-file
Else
Write to diff-rec-file
End-if
End-if

I can see some redundant code in above logic, but i think tat will be corrected by prasad

Please correct me if i am wrong.

Cheers
Ashwin

srinivas_443 · New User Joined: 19 Dec 2007 Posts: 11 Location: chennai

Hi Ashwin

Good idea.Thanks

Anuj Dhawan · Posted: Tue Feb 12, 2008 7:01 pm

Hi,

Well, for such a file matching Logic, don't You think.. both the files should be in sorted order (ofcourse on the same key). BTW, this topic has been discussed many times, please search.

There is a sticky in Mainframe COBOL Forum by Dick for a file matching program. Use that to give You a start & change the code as per Your needs..here is the link.

dick scherrer · Posted: Tue Feb 12, 2008 10:11 pm

Hello,