What I am trying t odo with this script here is parse through a lot of data, and generate sql queries to update the db with values that i'm getting while this script's running. however, its very slow at the moment. i need suggestions on how to speed this thing up :) 
#!/usr/bin/perl -w

use strict;

sub weekday
{
    my ($day, $month, $year) = @_;
    if ($month < 3) { $month += 12; --$year; }

    my $tmp = $day + int((13 * $month - 27)/5) + $year + int($year/4) 
+- int($year/100) + int($year/400);
    return ($tmp % 7);
}

my $days_back = shift || 120;

my ($start, $end);

my @days = ("Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat");
my @days_month = (31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
my ($day, $month, $year) = (localtime)[3,4,5];

# Adjust year and month to readable stuff
$year += 1900; $month++;

$end = sprintf("%d-%02d-%02d", $year,$month,$day);

$day -= $days_back;

# If we went below 1, then we're into prev month
# we while() here for when $days_back is larger than 1 month
while ($day < 1)
{
    # Don't forget to pad Feb for leap years
    if ($month == 3 && ($year % 4) == 0) { $days_month[1]++ }

    # deceremnt the month and calc the day
    $day += $days_month[--$month - 1];
    if ($month < 1) { $month = 12; $year--; }
}

$start = sprintf("%d-%02d-%02d", $year,$month,$day);

print"$start\n$end\n\n";
system("parsecache -f nlclick -s $start -e $end > nlclick.cache");
system("parsecache -f nlimage -s $start -e $end > nlopen.cache");

#print "$start\n$end\n\n";

for (my $i = 0; $i < $days_back; $i++)
{
    my $wday = weekday($day, $month, $year);
    if ($wday > 0 && $wday < 6)
    {
        my $date = sprintf("%d%02d%02d", $year,$month,$day);
    
        #print "$date\n";
        $_ = `report pattern --regex='nl=$date' --filter=nlimage --sum
+only < nlopen.cache`;
        my ($opens) = /(.*)/;
        if (defined($opens))
        {
            $_ = `report pattern --regex='nl=$date' --filter=standard 
+--sumonly < nlclick.cache`;
            my ($transfers) = /(.*)/;
            if (!defined($transfers)) { $transfers = 0 }
            
            printf("update msnNewsletter set open='%d', click='%d' whe
+re dateCreated like '%d-%02d-%02d%%';\n", $opens, $transfers,$year,$m
+onth,$day);
        }
    }

    if (++$day > $days_month[$month - 1])
    {
        $day = 1;
        if (++$month > 12) { $month = 1; $year++; }
    }
}

unlink "nlclick.cache";
unlink "nlopen.cache";

[download]
if you need to look at the report tool that im using there, tell me and i will post that as well.

In reply to Parsing a lot of data. Very slow. Need suggestions by vxp

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