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Spring Boot sort by nested Entity

I am trying to sort my API result by a nested entity field.
My Entities look like that:
#Entity
#Table(name = "book_item")
public class BookItem {
#Id
#Column(name = "id", nullable = false)
#GeneratedValue(strategy = GenerationType.AUTO)
private UUID id;
#ManyToOne
#NotNull
private Book book;
...
}
#Entity
#Table(name = "book")
#Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Book {
#Id
#Column(name = "id")
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator")
private Long id;
#Column(name = "title", nullable = false)
private String title;
private String subtitle;
#ManyToMany(fetch = FetchType.EAGER, cascade = { CascadeType.PERSIST, CascadeType.MERGE })
#JoinTable(name = "rel_book_author", joinColumns = #JoinColumn(name = "book_id"), inverseJoinColumns = #JoinColumn(name = "author_id"))
#Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
#JsonIgnoreProperties(value = { "books" }, allowSetters = true)
private Set<Author> authors = new HashSet<>();
#Column(name = "isbn", nullable = false)
private String isbn;
#Column(name = "pages", nullable = false)
private Integer pages;
...
}
Now I want to query all BookItems sorted by the Book titles.
My repository lloks like that:
public interface BookItemRepository extends JpaRepository<BookItem, UUID> {
#Query(
"select distinct b from BookItem b left join b.book.authors authors where (upper(authors.name) like upper(concat('%', ?2, '%')) or authors is NULL ) and upper(b.book.title) like upper(concat('%', ?1, '%'))"
)
Page<BookItem> findAllByTitleAndAuthor(String title, String name, Pageable pageable);
}
I've implemented an Angular component which does the following request:
GET http://localhost:9000/api/book/items?size=5&sort=title,asc
I get a 500 error code:
org.hibernate.QueryException: could not resolve property: title of: org.pickwicksoft.libraary.domain.BookItem [select distinct b from org.pickwicksoft.libraary.domain.BookItem b left join b.book.authors authors where (upper(authors.name) like upper(concat('%', ?2, '%')) or authors is NULL ) and upper(b.book.title) like upper(concat('%', ?1, '%')) order by b.title asc, b.id asc]; nested exception is java.lang.IllegalArgumentException
I also tried the following and it also does not work:
GET http://localhost:9000/api/book/items?size=5&sort=book_title,asc
How can I solve this problem?

Many to Many JPA join query

#Entity
#Table(name = "customer", schema = "customer")
public class Customer {
#Id
#GeneratedValue
#Column(columnDefinition = "uuid", updatable = false, name = "customer_id")
private UUID customerId;
private String name;
#ManyToMany(mappedBy = "bookMembers")
Set<Reservation> reservations
}
#Entity
#Table(name = "reservation", schema = "reservation")
#NoArgsConstructor
public class Reservation {
#Id
#GeneratedValue
#Column(columnDefinition = "uuid", updatable = false, name = "reservation_id")
private UUID reservationId;
#JoinColumn(name = "reservation_id")
#Column(name = "reserved_by_customer_id")
private UUID reservedByCustomerId;
#JoinColumn(name = "menu_id")
private UUID menuId;
#ManyToMany
#JoinTable(
name = "reservation_customer",
schema = "customer",
joinColumns = {#JoinColumn(name = "reservation_id")},
inverseJoinColumns = {#JoinColumn(name = "customer_id")}
)
private Set<Customer> reservationMembers = new HashSet<>();
}
Dao Entity
#Data
#AllArgsConstructor
public class MenuCount {
private UUID menuId;
private Long count;
}
Repository
public interface ReservationRepository extends JpaRepository<Reservation, UUID> {
#Query("select new com.de.dao.MenuCount(r.menuId, count(c.customerId)) from customer c join c.reservations r group by r.menuId")
List<MenuCount> getCustomerCountGroupByMenuId();
}
I am trying to get the total number of customers for each menu Id. But when running the code getting the below error
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'Repository': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalArgumentException: Validation failed for query for method public abstract java.util.List com.de.repository.Repository.getCustomerCountGroupByMenuId()!
Native -
select r.menuId, count(c.customerId) from Customer c join reservation_customer cr on c.customerId = cr.customerId join Reservation r on r.reservationId = cr.reservationId groupBy r.menuId;
Can I acheive the native query functionality using #Query() in JPA without creating an additional entity module

Hibernate join one to many by java

I'm using Hibernate and I have two tables:
Table A:
#Table(name = "users")
public class User extends BaseEntity {
#OneToMany(fetch = FetchType.LAZY, cascade=CascadeType.ALL)
#JoinColumn(name = "book_id")
private List<Book>book;
}
and
Table B
#Table(name = "books")
public class Book extends BaseEntity {
#Column(name = "nameOfBook")
private String nameOfBook;
#Column(name = "userId")
private String userId;
}
I have to do the following query:
select *
from users, books
where books.nameOfBook == 'duck' and users.id == books.userId
My problem that I have not understood how to convert the SQL in Java like this:
Subquery<String>query = query.subquery(String.class);
Root<Supplier> psFrom = supplierQuery.from(User.class);
Path<String> expression = psFrom.get("id");
supplierQuery.select(expression);

JPA multi fetch with #OrderColumn return multiple null value

Have 3 entities
Group
#Entity
#Table(name = "`group`")
public class Group implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id_group")
private Long id;
#OneToMany(mappedBy = "group",cascade = CascadeType.ALL,fetch = FetchType.EAGER)
#OrderColumn(name = "id_student")
private List<Student> students = new ArrayList<>();
#ManyToOne
#JoinColumn(name = "id_faculty")
private Faculty faculty;
.....getters/setters
}
Student
#Entity
#Table(name = "student")
#JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id", scope = Long.class)
public class Student implements Serializable {
#Id
#Column(name = "id_student")
private Long id;
......
#OneToMany(mappedBy = "student",cascade = CascadeType.ALL,fetch = FetchType.EAGER)
private List<Rating> ratings = new ArrayList<>();
#ManyToOne
#JoinColumn(name = "id_okr")
private OKR okr;
#ManyToOne
#JoinColumn(name = "id_group")
private Group group;
.....getters/setters
}
Rating
#Entity
#Table(name = "rating")
public class Rating implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id_rating")
private Long id;
#Temporal(TemporalType.DATE)
#Column
private Date date;
#ManyToOne
#JoinColumn(name = "id_student")
private Student student;
#ManyToOne
#JoinColumn(name = "id_paragraph")
private Paragraph paragraph;
.....getters/setters
}
JPA Query
#Query(value = "SELECT g FROM Group g INNER JOIN FETCH g.students s LEFT JOIN FETCH s.ratings r WHERE g.id = :id AND s.group.id = g.id AND (r.student.id = s.id AND r.date BETWEEN :startMonth and :endMonth OR r IS NULL) GROUP BY s.id")
Group findGroupByStudentGroupId(#Param("id") Long id ,#Param("startMonth") Date startMonth, #Param("endMonth") Date endMonth );
I have the student with id 8000 and after extracting query the result list contains 8001 elements which contain 8 students that I have and 7993 null values. If I remove annotation #OrderColumn I have MultiBagException(cannot simultaneously fetch). If add #OrderColumn to rating #OneToMany association in the entity Student I have null values in Rating collection and in Student collection.
For me, the logic of #OrderColumn which return null values as biggest id in collection seems very strange. Is any way how to solve it?
Hibernate version 5.1.0 Final
Spring Data JPA 1.8.2

As you are trying to fetch students with particular group and ratings, you can have your query fetch from student entity and have join on Ratings entity. You don't have to explicitly add join for group entity as it is already in many to one mapping with student.
You can Change your query as follows:
#Query(value = "SELECT s FROM Student s LEFT JOIN s.ratings r WHERE s.group.id = :id AND (r.date BETWEEN :startMonth and :endMonth OR r IS NULL) GROUP BY s.id")
List<Student> findGroupByStudentGroupId(#Param("id") Long id ,#Param("startMonth") Date startMonth, #Param("endMonth") Date endMonth );

Hibernate query to Sql query

My entity of product looks like below:
#Entity
#Table(name = "order")
public class OrderEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "order_id")
private Long id;
#ManyToMany(cascade = CascadeType.ALL)
#JoinTable(
name = "order_products",
joinColumns = #JoinColumn(name = "order_id", referencedColumnName = "order_id"),
inverseJoinColumns = #JoinColumn(name = "product_id", referencedColumnName = "id")
)
private Set<ProductEntity> products = new HashSet<>();
}
ProductEntity:
#Entity
#Table(name = "product")
public class ProductEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
#Column(unique = true)
private String name;
#ManyToMany(mappedBy = "products")
private Set<OrderEntity> orders = new HashSet<>();
}
I want to get all orders where product name is equal to wanted value. And I write sql query to get result from database, but I cannot write hibernate query for Spring Data JPA.
My query for postgreSQL looks like this:
SELECT o.order_id, op.product_id, p.name
FROM public.order o
INNER JOIN public.order_products op
ON p.order_id = op.product_id
INNER JOIN public.product p
ON op.product_id = p.id
WHERE p.name = 'Foo';
And this query return me an id of order, product_id and name of product. And this works. But I didn't know how to write this question as spring query using #Query.
I need a metohod in my repository:
#Repository
public interface OrderRepository extends JpaRepository<OrderEntity, Long> {
#Query("") <- place for my query in Hibernate sql
List<OrderEntity> findAllByProductName(#Param("name") String name);
}

try this: (it returns full OrderEntity objects )
#Query("select o from OrderEntity o join o.products prod where prod.name = :name")
List<OrderEntity> findAllByProductName(#Param("name") String name);
if you need fetch eager all data for products use : ....OrderEntity o join o.products... in query instead of OrderEntity o join o.products

This is a projection consisting of columns from many entties, so you would have to go for the Result Class strategy.
Basically, you create a POJO class with expected result fields an an equivalent constructor:
public class ResultClass{
private Integer orderId;
private Integer productId;
private String name;
public ResultClass(Integer orderId, Integer productId, String name){
// set the fields
}
}
Then you alter the query a bit:
SELECT new com.mypkg.ResultClass(o.order_id, op.product_id, p.name)
FROM public.order o
INNER JOIN public.order_products op
ON p.order_id = op.product_id
INNER JOIN public.product p
ON op.product_id = p.id
WHERE p.name = 'Foo';
And change the return type on the interface method:
#Repository
public interface OrderRepository extends JpaRepository<OrderEntity, Long> {
#Query("...")
List<ResultClass> findAllByProductName(#Param("name") String name);
}