Sometimes I want to find the longest string under a particular column within a rather large, unsorted CSV file (several GB).

This can be useful to know for specifying sane database column size restrictions, etc. I've also found myself doing variations on this theme - wanting to do a quick and dirty comparison or operation based on an attribute of a particular column or columns in a delimited file.

Typically I'll do something like this:

perl -F, -lane 'print $t = length $F[0] <= $t ? next LINE : length $F[0]' file.csv

Just wondering if anyone has a cleaner one-liner to accomplish this. There's got to be a sexier way. Or maybe just a more efficient way. Any ideas?

Strange things are afoot at the Circle-K.

In reply to Delimited File Analysis One-Liner? by temporal

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