Single Table Inheritance (Database Inheritance design options) pros and cons and in which case it used?

Question

Today, I studied about about 2 database design inheritance approaches:

1. Single Table Inheritance
2. Class Table Inheritance

In my student o

Answer 1

Single table inheritance is a good approach when the subclasses don't have many attributes or associations with other classes. Otherwise the table would be full of attributes that only make sense for some tuples of the table and you´ll need to add all kinds of constraints to check that they only contain values for tuples of the appropriate "type".

Also, all queries that only need to deal with instances of one of the subclass will need the additional clause to select them based on the type value.