The network diagram depicts the devices, components, and interrelationships of a network. To make things easier to understand, it employs network diagram symbols. As you may be aware, portraying computer connections grows increasingly difficult as time goes on, and communications networks are practically impossible to depict.
A database is a collection of structured data that is kept and organized electronically as part of a larger collection. In EdrawMax, you may depict databases using a variety of forms. For the type of data you're describing, there are a variety of database shapes to choose from. Other attributes, such as external data, can be used to select shapes.