Entity and Table annotations. Understanding the exact differences between them

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I am learning hibernate and have some questions about the differences between Entity and Table, and how they work together/independently?

Case 1:

@Entity
public class Person{
}

My understanding - 
Entity name - Person
Table name in db - person

Case 2:

@Entity(name = "people")
public class Person{
}

My understanding - 
Entity name - people
Table name in db - people

Case 3:

@Entity
@Table(name="people")
public class Person{
}

My understanding - 
Entity name - Person
Table name in db - people

Case 4:

@Entity(name = "person")
@Table(name = "people")
public class Person{
}

My understanding - 
Entity name - person
Table name in db - people

Case 5:

@Table(name="people")
public class Person{
}

My understanding - 
Entity name - ??
Table name in db - people

Is my understanding of these five cases correct? Is there anything else I should know about the working of Entity and Table?

annotations hibernate java
1 Answers

@Entity is used to declare a class can be managed by Hibernate. It also defines the entity name through its name attribute which is the name that we refer to when writing JPQL/HQL queries. If the entity name is not specified , it is default to the unqualified name of that entity class.

For example :

@Entity(name="People")
public class Person{
}

Then I need to use People to refer to this entity when writing a JPQL/HQL query :

select p from People p;

@Table defines the actual DB table name that an @Entity is mapped to through its name attribute. If it is not specified , its default value will be equal to the entity name (i.e @Entity 's name attribute)

Also @Table only make senses if @Entity is defined . Otherwise , just defining @Table without @Entity (i.e case 5) does not have any effect.

So to to summaries:

Case 1:

@Entity
public class Person {

}

Entity name = Person
DB Table name = Person

Case 2:

@Entity(name = "people")
public class Person {
}

Entity name = people
DB Table name  = people

Case 3:

@Entity
@Table(name="people")
public class Person{

}

Entity name = Person
DB Table name =  people

Case 4:

@Entity(name = "person")
@Table(name = "people")
public class Person{
}

Entity name = person
DB Table name = people

Case 5: Invalid

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