I created a simple form from a SQL Server datasource which had a binary field, I was able to allocate the file upload field to the binary field, but it didn't save any data into the datasource. I removed the file upload field and it stored the other fields.
I reported this as a bug two months ago and was told that I could do this by writing code. We bought Contour so that this could be done without writing code.
Blob storate isn't suported in the default sql datasource type, but if you change it to a a text field it should store the path of the file, would that work out for your case?
And the main use for these datasources is to integrate with already existing datasources (like legacy apps), if it's a new table why create a table and datasource? When you can simply create the form in Contour ...
The issue relates to Clients wanting to use their Umbraco sites for recruitment, and have candidates upload their CVs and Cover Letters. Yes Contour can create the form, but it cannot easily manage it. The standard entries section only lists the GUID path to the file. Yes you can export the list, but not the Files that were uploaded. The only way to get all the information from the form in one format is to store it all in a data source and then use a Dynamic Data / Lightswitch solution to access it.
The same would apply to images that are attached to forms, or files required in a Support situation.