my %log_data;
open FH, $file or die "Can't open $file: $!";
while (<FH>) {
 my ($net_id, $mdy, $item) = split /\|/;
 $log_data{$net_id}{$mdy}{$item} = $_;
}

# Then cycle through data you're searching for
# and save/process it if its in the %log_data array