Oracle: connection rate to the listener

A single line command to read the listener log, filter the message from a date (you can change it), and group by hour to count the connections:

adrci exec='set home diag/tnslsnr ; show alert -term -p \"' "MESSAGE_TEXT like \'%establish%\' and ORIGINATING_TIMESTAMP > \'2018-06-07 00:00:00\'" '\"' | awk '/establish/{sub(/:.*/,"",$2);print "connection/hour at "$1,$2":00-"$2":59"}' | uniq -c

Originally published on Twitter:

connection rate to the listener adrci exec='set home diag/tnslsnr ; show alert -term -p \"' "MESSAGE_TEXT like \'%establish%\' and ORIGINATING_TIMESTAMP > \'2018-06-07 00:00:00\'" '\"' | awk '/establish/{sub(/:.*/,"",$2);print "connection/hour at "$1,$2":00-"$2":59"}' | uniq -c

 — @FranckPachot