You're not checking any errors and don't have the RaiseError or PrintError attributes on your DBI object. I think that DBI has PrintError set to a true value by default, but I prefer to be explicit there:

my $dbh = DBI->connect('DBI:ODBC:MyDB',undef,undef,{RaiseError => 1});
...
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My wild guess is that either DBI does not like the trailing semicolon in your statement - maybe remove that from your statement. The other option is that the ODBC driver, for some weird reason, prefers % over * as a wildcard. The wildcard for Access is * while for most other SQL implementations is %.