my $dbhost = "database_host";
my $dbuser = "username";
my $dbpw = "password";
my $cafile = "/path_to_CA_file/ca-cert.pem";
#my $key = undef;
#my $cert = undef;
my $dbname = "dbname";
my $dbtable = "dbtable";

my $dbh = DBI->connect("DBI:mysql:database=$dbname;host=$dbhost;mysql_ssl=1;mysql_ssl_ca_file=$cafile","$dbuser", "$dbpw",{'RaiseError' => 1})
or die "Error in connecting to database";