A simple Perl script to count the number of times
individual keys lines have been seen.
It's perl as I often use if on "bare bones" servers
where there's little installed to count eg the
number of different HTTP status codes returned as
seen in the log files:
cat access.2011-08-24.log | \
awk '{print $9}' | \
distinct
distinct-keys, occurances
200,107875
500,459
503,4790
The script is so simple that it's a doddle to
make it fit your own needs.