#!/usr/bin/perl -w

use strict;
use warnings;

my @data_list = (
	{key => 'date', value => '2009-01-01'}, 
	{key => 'correct', value => 'some_data_here'}, 
	{key => 'date', value => '2009-01-02'}, 
	{key => 'correct', value => 'some_data_here_again'}
); # Presumption of your test data based on your code..


my ($cor, $date);
foreach my $data_pair(@data_list) {
	$cor = $data_pair->{value} if($data_pair->{key} eq 'correct');
	$date = $data_pair->{value} if($data_pair->{key} eq 'date');
	if($cor && $date) {
		# SQL Update goes here....
		print "Found a match for $date and $cor\n";	
		# Reset for the next loop
		($cor, $date) = (undef, undef);		
	}
}