Hi, I have a couple of questions surrounding the speeding up of a regex I've written. Please bear in mind I'm not a Perl guru so I'd like to learn a bit from the masters on how best to write more efficent code.

Here's a snippet of my code 

my @patterns = (
   qr/\bcreate\b/,
   qr/\bdrop\b/,
   qr/\bdelete\b/,
   qr/\bupdate\b/,
   qr/\binsert\b/,
);

open a database connection here (using Sybase::DBD) and
create a statement string to execute

$sth=$dbh->prepare("@sqlstatement");
$sth->execute;
while ($data = $sth->fetchrow_arrayref()) {
   next if($data->[10] =~ /tempdb/i);
   for ($loop_index = 0; $loop_index < $#patterns; $loop_index++) {
      if($data->[13] =~ /$patterns[$loop_index]/i) { print "$data->[3]
+ $data->[9] $data->[10] $data->[13]\n";
 }
   }
}

[download]
This extracts an audit trail from a sybase database and examines each row via the regex above. It produces the output I want but I can't help feeling there's a more efficient way of doing the regex bit.

The first question is , if I wanted to get the keywords from a file (so I can build up a dictionary of keywords to search for) instead of hardcoding them as complied regular expressions as in the code above , how would I do this ? e.g. assume my keyword input file would look like this 

create
delete
insert
update
drop

[download]

Is there a more efficient way of doing the regex ?... I read somewhere about the possibility of using the study function to improve the performance.

Any help appreciated, thanks in advance

In reply to speeding up a regex by Anonymous Monk

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