With the recent developments in Adobe Camapign Standard- does it support complex data models like in V6?. I am wondering using ACS can we have a back-end SQL database and manage the data flow into the database using ASC (using Adobe I/O?) without the need of another ETL tool?
ASC is very limited if you are working with any complex system, You can't extract the whole data model from ASC on a regular basis to an external database. As florent mentioned its not possible to use FDA although you can use flat files in ASC.
Adobe Io is good if you are using ASC data over your website i.e AEM or in Target or in Audience manager.
ASC have really nice capability for reporting(Adobe analytics API's) which is not available to classic users.
@Florent, Do you know any api or tool which we can use to enhance the calender's capabilities in classic version?
Currently in ACS you cannot use external data sources like FDA for v6. What you can do is add new resources or extend an existing resource with new fields, as described here in the doc: Custom resources