title: Difference between using relational database and relational database-object
body: <p>What's the diference between using relational database and relational database-object(hybrid).</p>
  
  <p>Im making an application of adverts. Using common relational database, i think I could make  tables of each type of adverts: cars,technology,estates,employment, services, this is the way a I do it.But reading about relational database-object I found that you can create a type field in the database(Oracle) that allows you to encapsulate another fields and methods, so what if I make only a table of adverts, knowing that all adverts have fields in common like title, description,the date it publish, images, but I can add a field that encapsulate another objects that will be cars,technology, employment, and inside of each one encapsulate attributes to them like
   cars(model,brand,price),
   technology(state,price,accesories,dimensions)
   emloyment(job,payment)</p>
  
  <p>Well this is the idea, actually for every advert you can actually enlarged the functionality, making a database for each one.
  My question is: what are the potencial problems using relational database-object?
  What is the best option?</p>