Question

I’d like to have a script that shows the users who are logged in to my server through MySQL. Right now I use

show processlist;

and manually open each of the BLOBs to see which entries correspond to the server itself, which correspond to robots, which correspond to inactive users, and so forth. But there has to be a better way!

I was imagining a Perl script, but perhaps there’s a better way. Surely it is not rare to wonder who is logged in — is there some standard tool?

Answer 1

Does something like this help?

#!/usr/bin/perl

use strict;
use warnings;
use DBI;

my $user = "root";
my $pass = "password";
my $db = "information_schema";

my $dbh = DBI->connect("DBI:mysql:$db", $user, $pass)
        or die "Connection error: $DBI::errstr\n";
my $sql = "show processlist";


my $sth = $dbh->prepare($sql);
$sth->execute() or die "SQL error: $DBI::errstr\n";

my %user;

while (my @row = $sth->fetchrow_array()) {
        $user{$row[1]}++;
}

print "MySQL - Logged in users\n";
print "=" x 15, "\n";

for my $x (keys %user) {
        print "$x - $user{$x} connections\n";
}

Result:

MySQL - Logged in users
===============
ndoutils - 6 connections
root - 1 connections
nagiosql - 5 connections