SqlException: An object or column name is missing or empty.

Feeds fail with the following exception when deploying data:

"An object or column name is missing or empty. For SELECT INTO statements, verify each column has a name. For other statements, look for empty alias names. Aliases defined as "" or [] are not allowed. Change the alias to a valid name."

This is an issue with the ETL Engine 3.0.1 sort capabilities introduced here.

This has been solved in the ETL Engine 3.0.2.