Your additions to the regex make it unsafe because they are not terminated with $.Try 

#!perl
use strict;

my @ids = qw( 
spam-IUiA-_bUe0eN.gz
badh-Xh-Vzy9BSsHN
banned-8KuHlZuzBCaA
virus-gUS5QeJ_ayqZ
virus-gUS5QeJ_ayqZ;stopme );

for my $id (@ids){
  if ($id =~ /^(?:spam|badh|banned|virus)-[a-zA-Z0-9-_.]+$/) {
    print "OK : $id\n";
  } else {
    print "ERROR : Invalid id '$id'\n";
  }
}

[download]
poj

In reply to Re^11: INSERT file contents inside a table by poj
in thread INSERT file contents inside a table by theravadamonk

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