Lately, I've been trying to improve my skills and style in Perl.  Much of what I work on in Perl involves the CGI module.  So I would like to get some criticisms of my skills and style in writing a CGI Perl script.  Below is a sample of one of my simpler CGI scripts--it's a collection of snippets I've culled from books and web sites and modified.  It's a bit long, but I think posting it could be useful to monks who are new to the CGI perl module in that this script does work and is complete.  But feedback from more senior monks would be useful to me in particular.

I'd like all the criticisms I can get, but please don't feel obligated to review and comment on everything.  You could just pick out one line that stands out.  I would like comments on functionality, documentation, layout, spacing, etc.  No criticism will be considered too minor.  Thanks in advance.

-Spenser

#!/usr/bin/perl -w

# Program Name:  emp-list.cgi

# Primary Programmer:  Spenser

# Description of Program:
# This is a Perl (vs. 5) script which lists
# employees in a web format with hyper-links
# to another script/web page containing details.

# Set Perl Modules & Initial Variables
use strict;
use CGI qw/:standard/;
use DBI;

my $q = new CGI;
my $sort = param("sort") || "emp_last";
my $style = "<link rel='stylesheet' href='/styles/hr.css' type='text/c
+ss' />";

# Extract list of employees from mySQL
my $dbh = DBI->connect("DBI:mysql:sys_main:localhost", "user", "passwo
+rd")
          || die "Could not connect to database: " . DBI->errstr;
my $sql_stmnt = "SELECT emp_id, CONCAT(emp_last, ', ', emp_first), dep
+t_name
                 FROM sys_main.humans, sys_main.depts 
                 WHERE status='AV' AND dept_id=dept
                 ORDER BY '$sort'";
my $sth = $dbh->prepare($sql_stmnt);
$sth->execute();

# Create web page for displaying data to user
print
   $q->header( -type=>'text/html'), "\n\n",

   $q->start_html(-title=>'Employee Table', -bgcolor=>'#FFFFFF', 
                  -link=>'#4682B4', -vlink=>'#5F9EA0',
                  -alink=>'#1E90FF'), "\n\n",
   $style, "\n\n",

   $q->start_table({-width=>'450', -border=>'0',
                    -cellpadding=>'2', -cellspacing=>'0'}), "\n\n",

   $q->start_Tr,
   $q->start_td({-align=>'left', -width=>'100%',
                 -colspan=>'4'}),  "\n",
   "<span class=section-heading>Employee Table</span>",
   $q->hr, "\n\n",
   $q->p("To access an employee\'s records, just click on their name
          in the table below. &nbsp;To re-sort the list, click
          on the columnn heading to sort by"),  "\n",
   $q->hr, $q->end_td, $q->end_Tr, "\n\n",

   $q->start_Tr, $q->start_td({-align=>'left', -width=>'20%'}), "\n",
   $q->a({-href=>"emp-list.cgi?sort=emp_last"},
   "<span class=col-heading>Emp. ID</span>"),  "\n",
   $q->end_td, "\n",

   $q->start_td({-align=>'left', -width=>'45%', -colspan=>'2'}),
   $q->a({-href=>"emp-list.cgi?sort=emp_id"},
   "<span class=col-heading>Employee Name</span>"), "\n",
   $q->end_td, "\n",

   $q->start_td({-align=>'left', -width=>'35%'}),
   $q->a({-href=>"emp-list.cgi?sort=dept"},
   "<span class=col-heading>Department</span>"), "\n",
   $q->end_td, $q->end_Tr, "\n\n",

   $q->start_Tr,
   $q->start_td({-align=>'left', -width=>'100%',
                 -colspan=>'4'}), "\n",
   $q->hr, $q->end_td, $q->end_Tr, "\n\n";

# Loop through employee data and display info.
while (@_ = $sth->fetchrow_array()) {
   $emp_id = $_[0];
   $emp_name = $_[1];
   $dept = $_[2];

   print
     $q->start_Tr,
     $q->start_td({-align=>'left', -width=>'20%'}), "\n",
     $q->a({-href=>"emp-view.cgi?emp_id=$emp_id"}, "$emp_id"), "\n",
     $q->end_td, "\n",

     $q->start_td({-align=>'left', -width=>'45%', -colspan=>'2'}),
     $q->a({-href=>"emp-view.cgi?emp_id=$emp_id"}, "$emp_name"), "\n",
     $q->end_td, "\n",

     $q->start_td({-align=>'left', -width=>'35%'}), "\n",
     "$dept", $q->end_td, $q->end_Tr, "\n\n";  }

$sth->finish();
$dbh->disconnect();

print
   $q->start_Tr,
   $q->start_td({-align=>'right', -width=>'100%', -colspan=>'4'}),
   $q->hr, "\n",
   $q->img({-src=>'/images/poweredbymysql.gif',
            -align=>'right', -border=>'0',
            -alt=>'This page was created by Perl & mySQL'}),
   $q->end_td, $q->end_Tr, "\n\n",

   $q->end_table, "\n",
   $q->end_html;

exit;

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In reply to A Matter of Style in CGI by Spenser

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