Confused...My previous code just traverse till the end of DATA and just displays the end data. Its not performing what I am willing to do.

my $x=0;
while(<DATA>){
    next unless /\w/;
    my($server,$datetime,$metric,$value) = (split)[0,1,2,3];
    $value =~ s/,//g ;
    my $ddhh = substr $datetime,0,13;
    my $dd   = substr $datetime,0,10;
    $d{$dd    }{$server}{$metric}{max} = ($x < $value) ? $value : $x;
    $d{$dd    }{$server}{$metric}{min} = ($x > $value) ? $value : $x ;
    $h{$ddhh  }{$server}{$metric}{max} = ($x < $value) ? $value : $x;
    $h{$ddhh  }{$server}{$metric}{min} = ($x > $value) ? $value : $x ;
    $ser{$server} = 1;
    $met{$metric} = 1;
}
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In above code $x < $value always holds true and just traverse till end of DATA...it doesn't find the maximum value. If you don't mind can you please provide me the pseudo-code OR any hints to achieve it?

Not code, but look at autovivication, defined, and exists. Basically, unless you set a variable to some value, it is undefined. defined allows you to test for that condition. If a min/max value is not defined when you first use it, would it not make sense to set them both to $value?

--MidLifeXis