MS SQL Server and Unicode

We’re utilizing a MS SQL Server db as a datawarehouse and the DF API’s are producing results for some tables and not for others. It turns out the tables that DF is not sending data back from contain unicode characters.

In reading this Introduction(http://php.net/manual/en/ref.pdo-dblib.php) from the middleware we’re using it seems this lib might not be the best option to use. I’m wondering whether anyone knows if the unicode issue is because of the dblib or is a dreamfactory issue? Additionally, I’m wondering whether the ODBC option is a better approach and “might” resolve this issue or not?