my $session = shift;    # value we want to query for

my $dbh = DBI->connect("DBI:mysql:$database:$server","$username","$password");

&extract_hash;

unless ($session_hash{$session}) { &inject; }

$dbh->disconnect();

sub extract_hash {
        my $select_query = "SELECT session FROM stats";
        my $sth0 = $dbh->prepare($select_query);
        $sth0->execute();
        while (@data = $sth0->fetchrow_array) {
                $session_hash{$data[0]} = 1;
        }
}

sub inject {
        my $insert_stmt = "INSERT INTO stats (date,
                                                time,
                                                user,
                                                session,
                                                action,
                                                type,
                                                zone) VALUES (?,?,?,?,?,?,?)";
        my $sth2 = $dbh->prepare($insert_stmt);
        $sth2->execute($date,$time,$user,$session,$action,$type,$zone);
}