If you are using the DNN default import/export option supported by Store, just be careful because Store won't check whether he categories/products you are importing are already existing or not; it will simply import entire file contents. Since each category/product is assigned its unique "ID" inside the Categories/Products table, duplicate title's don't matter and hence everytime you perform import export you have to manually remove existing categories/products from the file before you perform import. It will not update existing category/product, it will create a new one.

Is there a way to use Microsoft's SQL Server Management Studio to import products into the store using an excel file? Do you have an example template I can use to build the bulk upload? You can deffinately import data into the database using an excel file in Microsoft's SQL Server Management Studio, here's how you import:

In Microsoft's SQL Server Management Studio go to Database --> Select Task --> then Import Data --> finally Choose Excel File.

I just need to figure out how to setup the columns in the excel file (usually along the top) and reference the Store_Products Table.