Hibernate one-to-many mapping

A mapping type classification

1 one-to-many

2 Many-to-one

3 One-to-one

4 Many-to-many (many-to-many)

 

Two-to-many mapping introduction

1 life example

 

2 Specific methods

In the database, a one-to-many relationship can be expressed by adding primary and foreign key associations.

 

In Java code, it is implemented by one party holding multiple parties, that is, using the <set> element in the "one" side to represent the object that holds the "many" side.