Storing of data in the database - Any restrictions



I am planning to create an application with flight data which can be consumed from flight aware api.
What information I can store in my database ? For example,
AB1234 2/6/2014 - Is the flight.
I want to add some parameters of my own and store in my database to create a mashup.
Is there any restriction in what data can be persisted, any documentation available for this ?



There are no restrictions on what you can store. You can persist whatever you want that you retrieve from FlightXML, though you should obviously take care to avoid serving your users stale data about flights in order to avoid a poor experience for them.