That could be a hard problem, depending on what you need the filtered data for. My usual method is to use a $hash{$line}++ type method to find dupes, but that's going to eat a lot of ram (the problem you're having now I guess) unless the lines have some identifier that you can use instead.

One option might be to build a $digest = Digest::MD5->new() and count the digests. That could be really computationally expensive, especially for a file that big. I guess it depends what the lines look like. Would it be possible to include a few sample lines?

-Paul

In reply to Re: Find duplicate lines from the file and write it into new file. by jettero
in thread Find duplicate lines from the file and write it into new file. by anna_here

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