title: How to define entire database schema in Symfony 4?
body: <p>Is there a way to define the complete database schema in one go in Symfony 4?</p>
  
  <p>I understand that individual entities/objects can be created using the <code>make:entity</code> and <code>make:migration</code> commands but I'm wondering if I could just define the entire schema in one sitting and then use it to build the associated entities and database.</p>
  
  <p>I recall that in earlier versions of Symfony it was possible to define the entire schema in a YAML file and then just issue a build command.</p>