Integrate data from an external data source, without writing a line of code, and without duplicating any data into Salesforce with Lightning Connect.

I just did the tutorial in the below link and it's great way to get hands-on with Lightning Connect.

What You Will Learn:

+ Configure an external data source

+ Synchronize schema to create external objects in Salesforce

+ Create relationships to link external objects to each other and to standard objects

+ Integrate external objects with Chatter

+ See external objects in action in the Salesforce mobile app

Lightning Connect Tutorial