#! /usr/bin/perl

use strict;
use warnings;

my $file = './pfad/zu/html.datei';

open(R_HTML,"<$file") or die $!;
my $content = join("",<R_HTML);
close R_HTML;

my ($erstes_table) = $content =~ /(<table[^>]+>.*?<\/table>)/;

print $erstes_table;