The Azure Data Factory is a cloud service for processing structured and unstructured data from nearly any source. A Data Factory is made up of a Dataset, Pipeline, and Linked Services.
Azure Blob to Azure Data Lake Store
https://azure.microsoft.com/en-us/documentation/articles/data-factory-azure-datalake-connector/
Azure Data Lake Store to Azure Blob
https://azure.microsoft.com/en-us/documentation/articles/data-factory-azure-datalake-connector/
Column mapping
From above link:”The samples below are for Azure SQL and Azure Blob but are applicable to any data store that supports rectangular datasets. You will have to adjust dataset and linked service definitions in examples below to point to data in the relevant data source.”