You would follow this sample:
http://azure.microsoft.com/en-us/documentation/articles/data-factory-use-onpremises-datasources/
Essentially you use a Data Management Gateway service to live on premises to talk to SQL Server or to NTFS file system, to copy up to WASB blob storage.
I don't know the bit about multiple tables in one JSON document, but I believe it can process a folder of files by giving the folder path instead of the full file name. You may have to use multiple data sets to copy multiple tables.
Thanks, Jason
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