What is the purpose of CascadeType in Spring Data JPA / Hibernate?

CascadeType is an option that specifies how related entities should be treated...

let's say you have a one-to-many relationship between courses and students...

in your @Entity class you may have something like:

@OneToMany(cascade = CascadeType.ALL)

This is saying that every operation you perform on this entity, every associated entity will get the same treatement,

So if you delete a parent entity all of it's children (associations) will also get deleted.

Sometimes this makes sense. Sometimes it doesn't. BE CAREFUL in using this as it can have unexpected consequences...