Why do you need connect via a the socket file? Presumably your mysql instance is listening for connections on a particular port number (default is 3306). In which case, you could use the command line

mysql -h localhost -P <port> -u root --password=password nemo
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which would translate in DBI to

my $dbh = DBI->connect("DBI:mysql:database=nemo;host=localhost;port=$p
+ort", 'root', 'password', \%attr);
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