Inner join in spring boot data jpa - spring-boot

Question

I am using spring boot data jpa 1.4 and I'm fairly new to it.
My table definition is here. Its fairly simple, there are 2 tables (Groups and Users).
The group table contains group_id(primary key), group_name, group_active(values=Y/N).
The group table can ideally have only one row which is has group_active to 'Y', the rest should have 'N'
The user table contains user_id(primary key), user_name, group_id(foreign key from group).
Following are my entity classes
Group:
#Entity
#Table(schema = "HR", name = "GROUPS")
public class Group {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "GROUP_ID")
private Long id;
#Column(name = "GROUP_NAME")
private String name;
#Column(name = "GROUP_ACTIVE")
private String active;
User:
#Entity
#Table(schema = "HR", name = "USERS")
public class User {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "USER_ID")
private Long id;
#Column(name = "USER_NAME")
private String name;
#Column(name = "GROUP_ID")
private Long groupId;
#ManyToMany
#JoinTable(
schema = "HR",
name = "GROUPS",
joinColumns = {#JoinColumn(table = "GROUPS", name = "GROUP_ID", insertable = false, updatable = false)},
inverseJoinColumns = {#JoinColumn(table = "USERS", name = "GROUP_ID", insertable = false, updatable = false)}
)
#WhereJoinTable(clause = "GROUP_ACTIVE='Y'")
private List<Group> group;
Repository class:
public interface UserRepository extends CrudRepository<User, Long>{
List<User> findByName (String name);
}
Query: This is the query I want to execute, which is a simple inner join.
SELECT U.*
FROM HR.USER U, HR.GROUP G
WHERE U.GROUP_ID=G.GROUP_ID
AND G.GROUP_ACTIVE='Y'
AND U.USER_NAME=?
What would be the correct way to write the #JoinTable or #JoinColumn such that I always get back one user that belongs to the active group with the name ?

Answer 1

I have done some tests based on your set-up and the solution would need to use filters (assuming there is only one Group with Group_Activity = 'Y'):
Group Entity
#Entity
#Table(schema = "HR", name = "GROUPS")
public class Group {
#OneToMany(mappedBy = "group")
#Filter(name = "activityFilter")
private Set<User> users;
User Entity
#Entity
#Table(schema = "HR", name = "USERS")
#FilterDef(name="activityFilter"
, defaultCondition="group_id =
(select g.id from groups g where g.GROUP_ACTIVE='Y')")
public class User {
#ManyToOne
#JoinColumn(name = "group_id")
private Group group;
When making a query
session.enableFilter("activityFilter");
session.createQuery("select u from Group g inner join g.users u where u.user_name = :userName");
Additionally if there are many groups with activity = 'Y' then try this:
#FilterDef(name="activityFilter"
, defaultCondition="group_id in
(select g.id from group g where g.GROUP_ACTIVE='Y')")