Dependent Children should not have their own Hubs. They are not Business Concepts and as such should not be a Business Key by themselves. They only make sense when associated with a Business concept. One example is Line Items in a Order. The Line Item in Order by itself does not make sense. It needs to … Data Vault Anti-pattern: Creating Hubs for Dependent Children
Why would you do that? HashKeys and HashDiffs are binary generated using a hashing algorithm like MD5 or SHA-1. Just store them as binary and effectively halve your storage and double your I/O! No need to convert them to the Char to store them as Varchar.
By using the Load Date we should be able to identify all the Data that was loaded into DV in that particular batch. If the Load Date is some else, for e.g. the Load Date from the ETL tool, the entire batch in DV can not identified using the Load Date.