使用不同的列值作为JPA实体类ID

Question

I have a situation where I have a join table defined in the database but not both of the single tables referenced in the join. For example:

Student_Course
--------------
studentID
courseID

Course
------
courseID
title
description

Normally (using proper normalization) you would also have a Student table, and the Student_Course table would join Course and Student:

Student
-------
studentID

Is there a way in JPA with annotations (or otherwise) to pull unique studentIDs out of the Student_Course table and create an Entity class of Student, but also use Student_Course as a join table? In SQL I would just use the SELECT DISTINCT statement. I do not have control over the database and design, so I'm stuck with this.

Normally, I would use the @JoinTable in the Student and Course classes to reference the Student_Course table.

Thanks!

Answer 1

The easiest solution is to create a database view out of your select distinct sql query, and map this view to an jpa entity.

A drawback is that creating the Student entity might not be possible from JPA (i know some database support inserting data in views, but i've never used this functionnality)