Hi,   Complex types are generally used to aggregate the characteristics of an object, for example: Based on: https://impala.apache.org/docs/build/html/topics/impala_struct.html#struct type: current_address STRUCT < street_address: STRUCT <street_number: INT, street_name: STRING, street_type: STRING>, country: STRING, postal_code: STRING> So now we have the 'current_address' attribute and its members grouped. This is not only organizational, but also has an impact on the performance of the processes related to this table. When you want to retrieve a data it can be done like this: SELECT id, name, current_address.street_address.street_number, current_address.street_address.street_name, current_address.street_address.street_type, current_address.country, current_address.postal_code FROM struct_demo;   Despite the example they are giving, it refers to Apache Impala the concept is the same applied to Spark. Hope this helps. ... View more