That question is hard to answer without any more details about the DBMS and encryption used.
In addition to that, I believe QV won't offer you any specialized functions besides the features offered by your DMBS and database driver. So you might better off getting help in a specialized forum for your specific DBMS, e.g. Microsoft SQL Server (of course, first place to ask would be your local Db administrator). As soon as you can access the data decrypted via the database ODBC / OLEDB driver, you should be able to access your data also from QV load script.