I work with spreadsheets for my business. The source files start out as csv, but change when I save them as spreadsheets. The spreadsheets are not used for math functions, only products & attributes. My business is an e-commerce site. Occasionally, items I have on my site become unavailable, so I need to update to remove the items. The problem is that I have so many items loaded, a 4 digit number, and the source files go into 5 digit numbers. It takes hours to manually do a visual comparison of product codes. Is there a program to compare 2 files for matching entries to flag the lines in the smaller file that either are or are not in the larger file?

You can use meld for this. It visually shows you the difference, and you can update one or the other with individual changes if you want. It's available in most distributions repository for installation.

If you are looking to delete items and the file is too large verify manually, you should be using a data base system. How do you verify the changes (deletions) are effective?

Actually if you store the copies in a spreadsheet, then the lookup fucntion should do.

OK

Have you tried the OpenOffice.org spreadsheet facility Edit -> Compare?

At a glance, I am not sure meld will really help, but I will look again later. It does not seem to be on this DVD, but I can check others. I run on a live DVD, not installed. I was having trouble trying to multi-task, looking into meld while testing compare. I don't actually delete any items. Instead, I simply switch them to unavailable. In the admin area, I can see the availability status as yes or no. I tried compare both ways, from the small & from the large. In each case, it gave me a list of several deleted lines & numerous changes it was making. It kept crashing my system & I was unable to determine the cause or reason for the changes. Basically, I am hoping to find a way to distinguish the product codes that I need to switch off from those that I don't.