IIRC , the original patterns are pulled from a database, but in the above case pulling the patterns from a file each time could perhaps be avoided by reading them all in at once:

open my $p, "< ". shift @ARGV
   or die "could not open pattern file: $!";
my @patterns = <$p>;
chomp @patterns;

for my $filename (@ARGV) {
    open my $f, "< $filename" or die "could not open $filename: $!";
    my @lines = <$f>;
    for my $pattern (@patterns) {
        printf "%s has %d matches for pattern /%s/\n",
        $filename,
        scalar(grep /$pattern/, @lines),
        $pattern;
    }
}
[download]

Going back to the original pulling patterns from a db gives us:

# get column 0 from all result rows simultaneously....
my $results = $sth->fetchall_arrayref([0]);
# error check here?
# results are ref to array of hashes, so convert to array
# we could avoid this and use "results" directly
my @patterns = map { $_->[0] } @$results;

for my $filename (@ARGV) {
    open my $f, "< $filename" or die "could not open $filename: $!";
    my @lines = <$f>;
    for my $pattern (@patterns) {
        printf "%s has %d matches for pattern /%s/\n",
        $filename,
        scalar(grep /$pattern/, @lines),
        $pattern;
    }
}
[download]

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

Outside of code tags, you may need to use entities for some characters:

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.