Incidentally, you can pass a query as a parameter to `mysql` with -e, you don't need to pipe it in; and -N suppresses column headings, so you could use that ins

Incidentally, you can pass a query as a parameter to `mysql` with -e, you don't need to pipe it in; and -N suppresses column headings, so you could use that instead of`tail`. ... also, you can pass -l (lowercase L) to `perl` to enable automatic line-end processing, which autochomps each line in the input (and sets the output record separator so echo() includes a trailing newline, not that it matters here). And FWIW you're not actually using -a (autosplit each line into @F) here - but you could use it instead of `cut`, and it does imply -n; you might not need -f either, unless you actually have a sitecustomize.pl for it to disable. So: $ mysql -Ne 'DESCRIBE table' | perl -ale 'push @fields, $F[0]; END { print qq/SELECT MAX(/ . join(" + ", map { qq/CHAR_LENGTH($_)/ } @fields) . qq/) FROM table/ }' (I could golf it further, but I think that covers the stuff you might actually find useful. I blame my perlmonks days...)