The other messages come from the if line in

sub create_table ($) {
  my($table_name) = $_;

  if (my $table_name eq /Doncaster_Deaths_1975_onwards_slim_D/){
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it's a wierd onstruction: you declare a local variable (unitialised) and compare it to the result of matching $_ against Doncaster_etc.

You probably meant to compare the argument of create_table to the string "Doncaster...etc...". Please note that the construction /regex/ is a shorthand for m/regex/ that conares the value of $_ to the regular expression. Look at perldoc perlre for more information.

Try something like:

sub create_table ($) {
  my($table_name) = $_;

  if ($table_name eq "Doncaster_Deaths_1975_onwards_slim_D"){
[download]

and the last two messages should disappear.