sub get_time_from_local_time_string {
   my ($time_string) = @_;

   my ($M, $D, $Y, $h, $m, $s) = 
      $time_string =~ m{(\d+)-(\d+)-(\d+) (\d+):(\d+):(\d+)};

   return timelocal($s, $m, $h, $D, $M-1, $Y);
}
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I don't know much about database dates, but if you can get it from the database as a number instead of as a string, it would be more reliable and faster.